Guide · 9 min read

Customer interviews and win/loss research: hearing why customers choose you, or don't.

By Nona Stabel and Carlijn Hofland · 30 October 2026

In short: Customer interviews and win/loss research let you hear, in customers' own words, why they chose you, a competitor or doing nothing. Talk to won customers, lost deals, postponed decisions and customers who left. Ask about the trigger, the alternatives and what tipped the balance, write down exactly what they say, and only then look for patterns.

Most B2B organisations think they know why customers choose them. Ask leadership, marketing and sales and you'll get three answers: quality, the personal approach, the price. Whether customers see it that way, hardly anyone knows. Nobody ever went and asked.

This guide shows how to do just that. Who to talk to, how to approach them, which questions to ask, and how to get from a pile of conversations to a choice that sharpens your positioning and your sales.

Why you need to ask customers

A team that tells the same story is a good start. But agreement inside the team doesn't tell you whether the story is right. A whole team can share the same wrong assumption, for example that customers choose on price, when they really choose for speed or a fixed point of contact.

Customer interviews test the story from the outside. Win/loss research is one form of it: you don't only talk to customers who chose you, but also to organisations that chose someone else, or put the decision off. That's exactly where you hear what your story is missing.

Who to talk to

Talk to four groups. Each one tells you something different:

Best customers: why did they choose you, and what keeps them? This is where you hear what really sets you apart.
Lost deals: who or what did they choose instead, and why? This is where you hear where your story or offer falls short.
Postponed decisions: why did they choose to do nothing? Often that's the real alternative, not the competitor.
Customers who left: what did they expect, and what did they get? This is where you hear whether promise and delivery match.

Start with six to ten conversations in total, spread across the groups. Ideally decisions from the past twelve months, so people still remember them well. Talk to the person who made or strongly influenced the decision, not just the day-to-day user.

How to approach them

Ask personally: a short message from the account manager or managing director works better than a form.
Be clear about the purpose: “We want to understand better how organisations like yours choose. It isn't a sales call.”
Keep it short: thirty minutes, online or by phone.
Let someone else run the conversation: not the salesperson who won or lost the deal. People are more honest with someone who has no stake.
Thank them properly: share afterwards what you learned, or what you'll do differently.

The interview guide

Use fixed questions, so you can compare the conversations. Ask open questions and follow up on the first answer. The real answer usually comes with the second or third question.

Stage	Question	What to listen for
Trigger	What happened that made you start looking? Why then?	The trigger: a new director, a lost customer, a growth target. You'll use it later in your ideal customer profile.
Alternatives	Who or what else did you consider? Including doing it yourselves, or doing nothing?	The real alternative. Often not the competitor you expect.
Tipping point	What tipped the balance in the end? Can you name a moment?	Their exact words. Write them down verbatim.
Doubts	What were you unsure about? What almost stopped it going ahead?	Objections sales hears more often, and that your story has no answer to.
The story	How would you explain us to a colleague? What would you say differently from us?	The customer's words next to those on your website.

For a lost deal, ask the same questions plus one more: “What would have had to be different for you to choose us?” Record the conversation if they agree, or have a second person take verbatim notes.

How to analyse the conversations

Start with the exact words: list the key sentences from each conversation, without summarising them in your own language.
Look for patterns: what comes back in three or more conversations? That's a pattern. Something said once is a signal, not yet a conclusion.
Separate what was said from what you think: mark each insight as said verbatim, a pattern, or still an assumption.
Put it next to your story: what do the website, the sales deck and the proposal say? Where does that differ from what customers say?
Choose one to three things: what changes in the positioning, the story or the way you sell?

Example: how findings change a choice

A made-up example, for the fictional software company of sixty people from the guide How to build a commercial strategy. The team thought customers chose them for the software's features. After eight conversations, something else turned out to matter:

What customers said: five of the six won customers mentioned the roll-out without downtime: “we could just keep working.” Not one customer named a feature as the deciding factor.
What lost deals said: two organisations chose to do nothing, because they were afraid a new system would disrupt their operation.
What changed: the promise shifted from “the most complete software” to “live within six weeks, without your operation stopping”. Sales got a fixed question about previous implementations, and the website got a page about the roll-out.

Common mistakes

Only talking to happy customers. Then you hear what you already knew. Lost deals teach you the most.
Letting the salesperson interview. People are then kinder than they are honest.
Leading questions. “Was it our personal approach?” always gets a yes.
Summarising in your own words. Then exactly what you were looking for disappears: how the customer says it.
Changing nothing. Agree up front who decides what happens with the outcome.

The test: have you heard enough?

Have we talked to won customers, lost deals, postponed decisions and customers who left?
Did we talk to the people who made the decision?
Did we record their exact words?
Do we know, for each insight, whether it was said, is a pattern, or is still an assumption?
Can we name one to three things we'll now do differently?

Do it yourselves, or together?

You can run the conversations yourselves, if someone with no stake in the deal leads them and there's time to work them out properly. What's often harder is the next step: from what customers say to a choice that leadership, marketing and sales stand behind. In the Positioning sprint we start with these conversations and make that choice together in two to three weeks. Having only the conversations done is also possible: we call that Customer voice research.

Frequently asked questions about customer interviews and win/loss

What is win/loss research?

Conversations with organisations that chose you, chose someone else, or put the decision off. You ask about the trigger, the alternatives and what tipped the balance, so you can see why you win and lose.

How many conversations do you need?

Start with six to ten, spread across won customers, lost deals, postponed decisions and customers who left. At those numbers you often already see patterns. If you're still hearing new things, talk to more people.

Will lost prospects actually talk?

More often than you'd think, especially if you ask for thirty minutes, make clear it isn't a sales call, and have someone other than the salesperson run it.

Isn't a survey easier?

Easier, yes, but you miss the most important part: following up. In a survey a customer ticks “quality”. In a conversation you hear what they mean by it.

How often should you do this?

Once, properly, when you work on a new positioning, and then a few conversations each quarter. That way you notice in time when customers start choosing differently.

New guides and insights? Follow STOF to Grow on LinkedIn

Want to know why customers really choose you?

In a free 45-minute introductory call we look at what you already know, what's still an assumption, and what a good first step would be.

Bring your challenge to the table

Read on

Solution