What does a customer success manager (CSM) do? Role, strategy, and impact in SaaS

What is customer success?

Customer success is a proactive, relationship-focused business function dedicated to helping customers achieve their desired outcomes when using a product or service. In essence, Customer Success uses your product or service to drive value for the customer by ensuring they meet their objectives and find long-term success. It’s not just about solving issues; it’s about guiding customers to realize value continuously. Effective Customer Success management aligns the customer’s goals with the company’s goals, creating win-win outcomes – happier customers who stay longer, and a healthier, growing business. Ultimately, a strong Customer Success strategy reduces customer churn (loss of customers), lowers the need for constantly acquiring new customers, and generates more opportunities for upsells or cross-sells as satisfied customers expand their usage.

From my experience, with over a decade in customer service and the last three years building Thena, I’ve had hundreds of conversations with customer success leaders. And here’s the truth: great customer success is not about how fast tickets get closed or how polished your QBR slides look. It is about driving revenue. The best CS teams keep customers engaged with their purchase at every step. They don’t wait for issues. They lead with insights, highlight untapped value, and recommend solutions that move the customer’s business forward. In SaaS, that’s the beauty — when customers win, they expand. And when they expand, revenue follows. Customer Success should be the engine that powers that cycle.

Customer service vs customer success

Customer experience (CX) vs customer support:

Why customer success matters (especially for SaaS)

In the era of subscription-based and SaaS businesses, Customer success has emerged as mission-critical. Unlike traditional one-time sales models, SaaS and other recurring revenue companies live or die by retention and lifetime value. Here’s why Customer success is so important:

• Retention and churn reduction: Recurring-revenue businesses rely on keeping customers over the long term. Customer success directly impacts retention by making sure customers achieve value continuously – which gives them a reason to stay. A dedicated Customer success team proactively engages customers through onboarding, training, and ongoing support to prevent problems and dissatisfaction, drastically reducing the likelihood that customers will leave (churn). Studies show that losing customers is extremely costly – for instance, one analysis found it can take three new customers to replace the revenue of one lost customer. Customer success mitigates this by addressing issues early and often. A great example is Iris Software, which maintained a 98% annual customer retention rate by employing proactive Customer success strategies to keep clients happy and successful. In short, investing in Customer success means investing in keeping the customers you worked so hard to earn.

• Revenue growth and net revenue retention (NRR): Beyond just keeping customers, Customer success is a driver of expansion revenue. When customers see real value, they not only renew their subscriptions – they often purchase more (upgrade, add users, buy additional modules). This increases Net Revenue Retention (NRR), a key metric for SaaS that measures how much revenue you retain and grow from your existing customer base. An effective Customer success function is directly linked to higher NRR. By ensuring customers achieve outcomes, CSMs create opportunities for upsells and cross-sells in a way that feels natural (as the product genuinely helps the customer succeed). In fact, 94% of companies that measure Customer success impact use a revenue-based metric like NRR to gauge its effectiveness – underlining that Customer success is viewed as a revenue engine, not a cost center. High NRR is the hallmark of successful SaaS companies; it means the company is not just replacing lost revenue, but growing within its existing accounts. For example, HubSpot and Monday.com – two high-performing SaaS firms – boast net retention rates of about 104% and 112% respectively. Those numbers indicate that through strong customer success initiatives (like robust onboarding, customer education, and continual value delivery), these companies are expanding customer spend well above any losses. In practical terms, NRR above 100% implies that the company will grow annually even without adding new customers, simply because its current customers are sticking around and investing more. This kind of efficient growth is exactly what Customer success is meant to drive.

• SaaS economics and efficiency: For SaaS businesses, focusing on Customer success is not just nice-to-have – it’s essential for the economics to work. Acquiring new customers can be far more expensive than retaining and expanding existing ones. Investors and industry leaders know this, which is why they pay close attention to retention metrics. As Gainsight CEO Nick Mehta explains, the shift to subscription models forced companies to realize they must “focus on keeping and growing existing customers, not just on getting new customers”. This led to the rise of Customer success as a formal practice. High retention and NRR translate to more efficient growth – in fact, companies with industry-leading net retention (often 120%+ in top SaaS firms) grow much faster and more profitably, and thus command higher valuations. Major investors scrutinize net retention on earnings calls as a key indicator of a SaaS company’s health. The logic is simple: if your customers stick around and spend more over time, your business has a strong foundation. Customer success is the function that makes this happen by ensuring customers get ROI from the product continuously.

• Customer lifetime value and advocacy: A successful customer is a loyal customer – and often an advocate. By helping customers reach their goals, Customer success increases customer lifetime value (CLV) and turns customers into promoters. Satisfied customers are more likely to recommend your product to others or serve as positive references. This advocacy further lowers acquisition costs (essentially free marketing) and builds your brand reputation. As one industry expert put it, we are seeing a “Customer-Led Growth” revolution: retaining and expanding existing customers, and turning them into advocates, can become your #1 growth engine – it’s cheaper, faster, and more reliable than solely trying to win new business. In other words, doubling down on Customer success can drive a “flywheel” effect: great experiences lead to retention and expansion, which leads to referrals and positive word-of-mouth, which brings in more business organically.

A powerful example of this in action is Monday.com, which has reported net revenue retention rates of 112–117% across segments in recent quarters between Q2 2024 and Q1 2025. The company explicitly credits this growth to its Customer success motion, especially for mid-market and enterprise clients. Monday.com’s CSMs play a central role in not just onboarding and support, but in driving workflow expansion, increasing product adoption, and identifying upsell opportunities as customers grow. Their GTM model is built around “land and expand,” where CSMs are the key engine behind the “expand.” For their $100K+ ARR accounts—where NRR hits as high as 117%—CSMs ensure deep product value delivery, alignment with business outcomes, and proactive relationship growth. This shows how Customer Success can evolve into a strategic revenue function, not just a retention safety net.

In summary, Customer success is critical, especially for SaaS, because it directly tackles the twin goals of retaining customers and growing their value. It’s proactive insurance against churn, a catalyst for higher recurring revenue, and a strategy for sustainable growth. Companies that invest in Customer success see the payoff in metrics like lower churn rates and higher NRR, which ultimately means more predictable revenue and better profitability. No matter if you’re a Customer success Manager on the front lines, a founder scaling your SaaS startup, or a VC evaluating a company’s potential – a well-executed Customer success function is a strong indicator of long-term success. As the saying goes, your company’s success is intertwined with your customers’ success and Customer success is how you ensure both thrive together.

Who is a customer success manager?

A customer success manager (CSM) is not just a support rep with a fancy title. They are a strategic partner to the customer and an operator inside the business. Their goal is not to keep accounts from churning, it is to help customers grow, succeed, and generate value for both sides.

In SaaS, where revenue depends on renewals and expansion, the CSM plays a central role. They are often the closest person to the account, with a clear view of both the customer’s goals and the company’s product roadmap. This makes them uniquely positioned to influence outcomes that matter.

A strong CSM knows when to step in, what to recommend, and how to connect customer goals with product capabilities. They are part consultant, part project manager, and part revenue enabler. Their focus is clear: make the customer more successful with your product than they would be with anyone else.

What do customer success managers (CSMs) do?

Customer success Managers (CSMs) are the trusted guides steering customers toward long-term success. Their role isn’t to wait for fires—it’s to prevent them entirely while unlocking more value along the way.

1. Onboarding: the first win

CSMs lead the onboarding process, ensuring new customers quickly reach their first “aha!” moment—the point where they realize, “This product is exactly what I needed.” That includes training, setup support, and sharing best practices tailored to the customer’s goals.

2. Proactive engagement

Unlike support, CSMs don’t wait for trouble tickets. They regularly check in, review usage data, offer optimization suggestions, and surface helpful resources. The goal: stay ahead of potential churn triggers and always add value.

3. Customer health scoring

CSMs monitor account health using data: product usage trends, support history, feature adoption, and more. Accounts showing red flags—like drop-off in usage or negative feedback—are flagged for intervention. A well-built health score is like radar for at-risk customers.

4. Customer advocacy

CSMs are the internal voice of the customer. They surface feedback to product, share insights with marketing, and work with sales to ensure alignment. When decisions are made inside the company, they represent the customer’s interest—especially for high-value accounts.

5. Upselling & cross-selling

CSMs don’t “sell” in the traditional sense—but they are perfectly positioned to identify when a customer is ready for more. They spot opportunities for add-ons, higher tiers, or new features, and coordinate with sales or expansion teams to drive it home.

The levels and landscape of customer success roles

Customer success isn’t a one-size-fits-all title—it’s a layered function with distinct roles that evolve from tactical execution to strategic ownership. Here’s how the hierarchy breaks down:

1. Commercial / SMB CSM

This is the high-volume operator. Commercial or SMB CSMs manage dozens to hundreds of smaller accounts. The name of the game is efficiency and scale—think tech-touch engagement, automated playbooks, webinars, and self-service resources. These CSMs prioritize speed, responsiveness, and smart segmentation to drive retention across a broad base.

Key focus: Scalable onboarding, health monitoring, and churn prevention.

2. Enterprise / Strategic CSM

Fewer accounts, much deeper relationships. These CSMs manage a handful of high-value customers, often with complex needs and multi-threaded stakeholders. They act as trusted advisors, aligning product adoption with the client’s broader business goals. Strategic CSMs are often in the room for QBRs, renewal negotiations, and long-term roadmap planning.

Key focus: High-touch engagement, business outcomes, and account expansion.

3. Director of customer success

Now we’re talking team leadership. Directors manage a team of CSMs, oversee segment strategies (SMB, mid-market, enterprise), and own key metrics like retention, churn, and NRR. They’re the bridge between frontline teams and the executive layer—balancing people management with strategic execution.

Key Focus: Team performance, process optimization, and customer journey strategy.

4. VP of customer success

This is the strategic owner of the entire function. The VP defines the vision, org design, tech stack, and KPIs for Customer success. They align CS with revenue, product, and company-wide goals—often reporting directly to the CEO or COO. The best VPs operate with a growth mindset, treating CS as a revenue-generating engine, not a cost center.

Key focus: Cross-functional alignment, NRR growth, and board-level reporting.

The career path: from execution to strategy

Customer success careers follow a clear progression:
CSM → Senior CSM → Team Lead → Director → VP.

Early roles are hands-on—managing accounts, solving problems, driving usage. As you rise, the focus shifts to managing people, setting direction, and aligning CS with revenue goals. For ambitious professionals, it’s a path that leads straight to the executive table—with customer impact at the center of it all.

The huge impact of customer success on SaaS

NRR as the north star

In SaaS, Net revenue retention (NRR) isn’t just a metric—it’s the pulse of the business. NRR measures how much revenue you retain and expand from your existing customers over time. An NRR above 100% means your current customers are not only sticking around, they’re spending more. That’s SaaS gold.

Customer success is the engine behind that number.

• It reduces churn by ensuring customers see ongoing value.

• It drives expansion by uncovering upsell and cross-sell opportunities.

• It boosts loyalty by building real relationships—not just contracts.

Put simply: NRR rises when Customer success performs.

Top SaaS companies like Snowflake (NRR: ~168%) and Datadog (NRR: ~130%+) don’t just build great products—they pair them with elite CS functions that keep customers growing. In fact, most companies with 120%+ NRR have dedicated CS teams tied directly to expansion revenue. They’ve figured out what many still miss: success isn’t sold, it’s earned—every month, every quarter.

The SaaS business model: retention is everything

Traditional software was about the big sale: sell it once, cash the check, move on. SaaS flipped the game. Now it’s subscription-based. Revenue is earned over time, and renewals are the real battlefield.

And here’s the core truth:

“I think everyone is thinking this: in the SaaS world, your first sale is just the beginning. The real battle is won or lost in the renewals, and that's where customer success shines.”

Customer Success is the team keeping customers engaged, supported, and growing. Without it, churn creeps in, revenue leaks, and growth stalls. With it, customers thrive—and become your biggest growth lever.

The equation is brutally simple:
No retention → no SaaS business.
High NRR → high valuation.

Customer success is what tips the scale.

Challenges in today’s customer success landscape

1. The new business vs. existing business conundrum

Ask any SaaS leader where the energy goes—and too often, it’s into landing the next logo. New business gets the spotlight, the budget, the headcount. But here’s the irony: the existing customer base is the real growth engine, and neglecting it can be costly.

Picture this: a sales team pushes hard to close a flashy $500K deal, while a $300K renewal quietly churns due to lack of CS engagement. Net result? You’re still in the red. It's not just a hypothetical—many companies have felt the sting of prioritizing acquisition over retention. The smart ones know the two need to coexist, but few execute that balance well.

2. The evolving customer

Today’s customers aren’t just buyers—they’re experts. They’ve researched competitors, read reviews, and likely tested your product before talking to anyone. Expectations are sky-high. “Good enough” won’t cut it anymore.

They expect proactive engagement, personalized insights, and fast resolutions. CS teams now play in a world where customers demand outcomes, not just support. The bar is always rising—and standing still is falling behind.

3. Measuring impact

Here’s the perennial elephant in the room: proving Customer success ROI.

“This is a perennial challenge. How do we move from being seen as an expense to being a profit center? It's about tying every success metric directly back to revenue.”

CS teams often juggle renewals, adoption, advocacy—and yet, without a direct quota, they’re sometimes seen as soft contributors. The path forward is clarity: connect your work to NRR, upsell revenue, and churn prevention. Use data to tell the story.

The companies that do this well give CS a seat at the revenue table—not the cost table. It’s not just about happy customers. It’s about valuable, growing customers.

The relevance of customer success today

Economic headwinds: from growth to efficiency

In today’s market, the “grow at all costs” mindset is being replaced with a sharper focus on efficient, durable growth. Capital isn’t cheap anymore. Boards and investors want leaner burn, stronger retention, and more predictable revenue.

That’s exactly where customer success steps in.

When budgets are tight, every renewal matters. Expansion is cheaper than acquisition. And churn? It hurts more than ever. Customer success becomes the front line—not just for retention, but for preserving revenue and stabilizing growth when net-new deals slow down.

It’s no surprise that in economic slowdowns, companies that outperform are often the ones with mature CS functions.

The “stickiness” factor

Great Customer success doesn’t just retain customers—it makes them want to stay.

By ensuring customers hit their goals, stay engaged, and feel supported, CS teams increase stickiness: the sense that this product isn’t just useful—it’s essential. Sticky products don’t get replaced in a budget cut. They become embedded in workflows, teams, and strategy.

Customer success helps drive that by:

• Increasing product adoption

• Educating users on underutilized features

• Mapping product value to real business outcomes

The result? A product that’s harder to rip out, even when CFOs start tightening spend.

In this climate, Customer success isn’t a nice-to-have—it’s a revenue safeguard and a growth lever. As companies get leaner and smarter, the smartest bets are made on the customers they already have. And the team that protects and grows those bets? That’s Customer success.

Customer success tools and platforms

The Customer success tech stack has grown into a full ecosystem—designed to help teams stay proactive, drive outcomes, and operate at scale. Here's how it breaks down:

1. Core customer success platforms

These are the central hubs for CS operations. Tools like Gainsight, ChurnZero, and Catalyst are built to help teams manage workflows across accounts and lifecycles.

Common features include:

• Health scoring & customer segmentation

• Journey mapping & lifecycle automation

• Renewal forecasting & playbooks

• Integrations with CRMs and product data

They’re especially useful for mid- to late-stage CS teams with structured processes and multi-segment support.

2. Thena: purpose-built for modern B2B customer success

Thena is built from the ground up for B2B teams that live in Slack, Microsoft Teams, and email—where real customer conversations actually happen. It combines smart ticketing with account-centric views, giving CSMs everything they need in one place:

• Tickets, activities, notes, and customer fields all tied to the account

• Full visibility into past interactions, across channels

• AI summaries, AI actions, and AI workflows that fully offload operational work

• A shared workspace for success, support, and product teams to collaborate

With ticketing and account data unified, CSMs can track outcomes, flag risks, and drive expansion—all without bouncing across tools. It’s the control center for modern, multi-channel customer operations.

3. Analytics & BI tools

Platforms like Mixpanel, Amplitude, and Looker give teams insight into product usage, feature adoption, and behavioral patterns. These tools help inform health scores and signal when engagement is slipping—or primed for upsell.

4. Communication tools

Tools like Intercom, Pendo, and Customer.io help CSMs automate onboarding flows, send in-app nudges, and deliver personalized outreach—at scale. It’s how teams stay close to customers without burning out on manual follow-ups.

5. Ticketing systems

Tools like Zendesk and Freshdesk give support teams structure—but when disconnected from CS workflows, insights can get siloed. That’s why integration—or better yet, consolidation—is key. 

Try Thena today.

How AI is challenging the status quo

AI is rapidly reshaping the CS function—especially the tactical, repetitive side of the job. Think automated health score alerts, churn risk models, renewal forecasting, onboarding sequences, and follow-up emails. Tasks that once ate hours of CSM bandwidth are now being handled by smart systems in seconds.

That’s a disruption to the traditional CSM model. The spreadsheet-heavy, admin-oriented approach? It’s on the way out. AI is forcing teams to rethink how value is delivered—and who delivers it.

But it’s not a threat. It’s an upgrade.

The new role of the CSM

AI isn’t here to replace Customer success Managers—it’s here to elevate them.

The modern CSM will be less of a task executor and more of a strategic consultant. With AI handling the monitoring, nudging, and predictions, CSMs can focus on the human layer: the complex, nuanced conversations that drive true customer outcomes.

Think:

• Executive alignment calls

• Change management support

• Identifying new business use cases

• Acting as a bridge between product and the customer’s strategic goals

In other words, AI handles the “what” and “when.” The CSM focuses on the “why” and “how.”

The winners in this AI-powered future will be CS teams that embrace automation to enhance—not replace—human connection. The job isn’t going away. It’s just becoming more valuable, more consultative, and more critical to long-term success.

Call it CSM 2.0: powered by AI, driven by strategy.

Where do we stand today?

Customer success has come a long way—from being viewed as a post-sale support function to becoming a strategic pillar of revenue growth. It’s no longer just about keeping customers happy; it’s about keeping them successful, retained, and expanding.

We’ve unpacked its evolution:

• CSMs have shifted from reactive fixers to proactive advisors.

• The structure now spans from high-volume SMB support to executive-level ownership.

• In SaaS, NRR is king—and Customer success is the crown.

• The landscape is changing fast: customers are more demanding, budgets are tighter, and AI is redefining the tactical workload.

But that’s not a threat—it’s the opportunity.

The future of Customer success is leaner, smarter, and more strategic. AI will take over the repetitive tasks. CSMs will lean into deeper business impact. The companies that thrive will be the ones that treat Customer success not as a cost center, but as a core engine of growth.

"The best companies in the world aren't just selling a product—they're selling a promise. And customer success is the team that makes sure that promise is kept. That's where we stand today, and that's the future."

Conclusion

Customer Success is not a feel-good function. It is a revenue engine built on trust, insight, and action. In SaaS, where growth depends on retention and expansion, CS is the team that keeps the promise your product made. When done right, it doesn’t just reduce churn—it drives upsell, fuels loyalty, and turns customers into champions. That’s not support. That’s strategy.

“If you do not have a customer success culture, you will not survive. Customer success is the new growth engine.”
— Marc Benioff, Co-CEO of Salesforce