ICP stress test

Is Your B2B SaaS ICP Actually Working?

Your ICP isn't a list of companies that could buy from you. It's a decision about where your commercial effort should go.

An ICP can be theoretically correct and commercially worthless at the same time. That happens when it only describes industry, company size, geography, revenue and technology, but says nothing about the problem, the trigger, the urgency, the buying context, the reason companies choose you, or what your successful customers actually have in common.

So the useful question isn't whether your ICP is accurate. It's whether your ICP can change a sales decision this week.

An ICP that doesn't help sales decide who not to pursue isn't specific enough.

Written by Merel Roest, Founder & GTM Consultant at Blackbird GTM.

Your ICP may not be the problem you think it is

Most founders assume a weak ICP means the wrong industry or the wrong company size. That's rarely it. The definition is usually plausible, it just doesn't carry enough commercial information to act on.

The result is a team that can describe the target customer in a slide and still cannot tell, looking at two accounts, which one deserves the next four hours of effort. That's not a research problem. It's a decision problem.

If your ICP has never caused anyone to walk away from a deal, it isn't being used.

How do you recognise a weak ICP?

Five patterns show up again and again in B2B SaaS companies between €0-2M ARR.

Your ICP is too broad

Symptom: Deal cycles and win rates vary wildly with no clear explanation.
What to investigate: Which segments produced your last ten won deals, and which produced the losses.

If almost every plausible buyer fits, the ICP describes a market, not a focus. Breadth feels safe, but it moves the real prioritisation decision to whoever happens to be prospecting that day.

Your ICP describes companies, but not buying behaviour

Symptom: Every deal needs a custom pitch and a new business case.
What to investigate: The trigger, the internal owner and the alternative that was rejected in your best deals.

"B2B SaaS, 50-200 employees, Benelux" is a filter for a list, not an explanation of a purchase. It doesn't tell you what happened inside the company that made this problem worth solving now.

Your best customers don't clearly fit your ICP

Symptom: Your strongest references come from segments you don't actively target.
What to investigate: What those customers share beyond firmographics, and why they bought when they did.

This is the sharpest signal of all. If the customers who closed fastest, renewed and expanded sit outside your stated ICP, the document is describing an ambition rather than reality.

Sales doesn't use the ICP

Symptom: Marketing and sales describe the target customer differently.
What to investigate: Whether ICP criteria appear anywhere in your qualification and stage definitions.

An ICP that lives in a strategy deck and never appears in qualification, prospecting or pipeline reviews has no commercial function. Ask your team to name the criteria from memory. The answer tells you whether it exists in practice.

Your ICP helps nobody say no

Symptom: No opportunity is ever disqualified on fit, only on budget or timing.
What to investigate: How many deals you disqualified last quarter, and on what grounds.

The purpose of an ICP is exclusion. If nobody can name a company that is explicitly out of scope, you don't have an ICP, you have a description of your addressable market.

What your best customers actually tell you about your ICP

An ICP shouldn't be invented top-down. You almost always have enough evidence inside the business already, it just isn't collected in one place.

Take your best customers, not your biggest: the ones that closed at a reasonable pace, renewed, expanded and didn't drain delivery or support. Then look for patterns across sources, and do the same exercise in reverse for the customers that cost you more than they returned.

Won deals: what situation were they in when they started looking
Lost deals: what did the ones you lost have in common
Customer interviews: why did they buy, in their own words
Sales conversations: which problem statement created urgency
Customer Success: which customers get value fastest
Support: which customers create disproportionate cost
Inbound: which segments arrive already convinced
Partners: who refers whom, and why
Usage patterns: which accounts adopt without being pushed

Patterns in your existing customers beat assumptions in your positioning document.

ICP versus targeting

These are often used interchangeably, which is why targeting lists get treated as strategy.

ICP

Who is most likely to benefit and buy
Built on evidence from customers, deals and losses
Explains problem, trigger and buying context
Used to decide who not to pursue
Changes slowly, as understanding improves

Targeting

Which specific accounts you choose to approach
Built on lists, sources and account research
Explains sequencing, priority and coverage
Used to decide who to contact this quarter
Changes continuously, per campaign or quarter

A good ICP makes targeting better. It is not the same thing as an account list, and an account list can never replace it.

The Blackbird GTM ICP Stress Test

Seven questions. This isn't a theoretical checklist, the point is whether your ICP can change a sales decision.

01Who are your best customers?
02What do they have in common?
03Why did they buy?
04What triggered the purchase?
05What problem were they solving?
06Why did they choose you?
07Can sales use your ICP to decide who NOT to pursue?

If you can't answer the last question with a concrete example from the past month, your ICP is a description rather than a decision instrument.

How Blackbird GTM approaches it

The work is investigative, not definitional.

01Collect the evidence
Won and lost deals, customer interviews, sales calls, Customer Success and support signals, inbound and usage patterns.
02Find the patterns
Which situations, triggers and buying contexts repeat across your strongest customers, and which repeat across the painful ones.
03Turn patterns into criteria
Fit criteria that are observable before a company enters your pipeline, so they can be applied instead of debated.
04Make it a decision instrument
Wire the criteria into qualification, stage definitions and prospecting, including explicit reasons to disqualify.
05Separate ICP from targeting
Translate the ICP into an account approach without letting the list quietly become the strategy.

A good ICP is a commercial decision instrument

The test of an ICP is not how well it describes your market. It's whether two people, looking at the same account, reach the same conclusion about whether to invest effort in it.

Most companies don't need a new ICP document. They need to act on what their existing customer base already tells them, then be disciplined enough to say no to everything else.

About the author

Merel Roest

Founder & GTM Consultant, Blackbird GTM

Merel Roest has led B2B SaaS sales as Head of Sales, built and ran a €1.7M direct sales pipeline, grew ARR by 40% and increased average contract duration by 66%. She works with founders and commercial leaders on ICP, messaging, sales process, qualification and commercial organisation.

Where to look next

A weak ICP shows up first as erratic conversion, which is where why your pipeline isn't predictable starts.
An ICP only changes behaviour once it lands in qualification, see the leaks in your sales process.
If only the founder can judge fit, read founder-led sales without founder dependency.
ICP clarity is the first condition for whether you're ready for your first sales hire.

Not sure your ICP is working?

Blackbird GTM helps B2B SaaS companies identify which customers are most likely to buy, why they buy and where commercial focus is being wasted.