How Do I Run Effective Customer Interviews?

The 'Mom Test' and why compliments are dangerous

One of the biggest risks in early-stage business is receiving 'false positives'—compliments from people who want to be supportive but have no intention of buying. This is often called the 'Mom Test': if you tell someone your idea and ask 'do you think this is a good idea?', they will almost always say yes because they like you and want to be encouraging. This is not evidence; it is social politeness. The goal of a customer interview is to make it impossible for the person to lie to you by never mentioning your idea at all in the first half of the conversation.

Instead, talk about their life, their workflow, and their specific challenges. If you are building a tool for recruitment, don't ask if they like your tool; ask how they hired their last few employees. If they describe a painful and frustrating process, you have found a problem worth solving. If they say they use a simple solution and it works fine, your idea may not have a market. You are looking for 'hair-on-fire' problems—issues so pressing that the customer is already trying to solve them, even if the current solution is clunky.

A successful interview often feels like a casual conversation where you are doing the majority of the listening. If you find yourself talking more than the customer, you are pitching, not interviewing. Stop pitching and start digging into the details of their workflow. Compliments are the enemy of data; if a customer says 'that sounds great!', thank them and then immediately pivot back to their specific problems. Compliments are a polite way to end a conversation; data is what you need to build a business.

Recruiting the right people: Finding the 'Arena'

The quality of your data depends entirely on the quality of your respondents. You need to speak to people who are 'in the arena'—those who are currently experiencing the problem you want to solve. Avoid friends and family, as they are too biased to give you the hard truth. Instead, look for people who are actively seeking solutions. This might mean looking at niche forums, LinkedIn groups, or trade associations where people complain about specific inefficiencies.

When reaching out, be clear that you are not selling anything. People are much more willing to give a short amount of their time for 'research' or 'to share their expertise' than they are for a sales pitch. Frame the request around their expertise: 'I am researching how [specific industry] handles [specific problem] and would love to hear your perspective as an experienced professional'. This appeals to their ego and positions you as a student of the problem.

It is often suggested to speak to a series of people before drawing firm conclusions. You will know you have done enough when you start hearing the same problems and phrases repeated. This 'pattern recognition' is the foundation of a solid value proposition. If every recruiter mentions the exact same bottleneck in their first week of a new project, you know exactly what your product's headline feature should be.

Designing your script: Focus on 'Money and Time'

While you want the conversation to feel natural, you should have a list of 'anchor questions' to ensure you get the data you need. Good questions start with 'Tell me about the last time you...', 'How do you currently handle...', or 'What is the hardest part about...'. These questions force the respondent to tell stories rather than give one-word answers. Stories contain context, emotion, and detail that 'yes/no' answers lack.

Crucially, focus on the 'money and time'. Ask: 'How much does this problem cost the business?' or 'How much time does your team spend on this manual task?'. If they have already tried to solve the problem using other tools or by hiring external help, they have proven they have a budget for it. If they have only complained about it but haven't spent anything to fix it, it is likely not a priority. A problem that doesn't cost money or time is rarely a problem people will pay to solve.

Watch for emotional cues. When a respondent leans in, gets frustrated, or starts using strong language, you have hit a nerve. These emotional peaks often point to the most profitable features or messaging for your eventual business. The goal is to find the 'gap' between where they are now and where they want to be, and then build the bridge.

The difference between 'Opinion' and 'Evidence'

In your notes, separate what the person *said* they liked from what they *actually do*. An opinion is 'I think a mobile app would be great for this'. Evidence is 'I currently use a spreadsheet and it takes me several hours every week'. You build a business on evidence, not opinions. People are terrible at predicting their own future behaviour. They might say they 'would' pay for a feature, but when the invoice arrives, they find a reason not to.

Be wary of 'feature requests'. Customers are good at identifying their problems but often poor at designing the solutions. If a customer suggests a feature, ask 'Why would you need that?' to get back to the underlying problem. Often, a feature request is just a symptom of a deeper workflow issue that could be solved in a much simpler way. Your job is to understand the problem so deeply that you can design a solution that is better than anything they could have suggested.

Also, look for 'workarounds'. If you see a customer using a tool in a way it wasn't intended, or combining different pieces of software to get a job done, you have found a massive opportunity. A workaround is strong evidence that a dedicated solution is needed. It shows that the need is so great the user has spent time building their own 'makeshift' solution.

Commercial Reality: High-Value vs Low-Value Problems

Not all problems are worth solving. A high-value problem is one that is frequent, painful, and expensive. A low-value problem is one that is annoying but doesn't stop the business from functioning. Through your interviews, you are trying to categorise the problems you hear. If many people mention a problem but few have tried to fix it, it's a low-priority issue.

Consider the 'Sales Route'. How will you find these people later? If you find a significant problem during your interviews but realise that reaching those people at scale requires a substantial marketing budget you don't have, the idea might not be commercially viable for you. The interview phase is as much about validating the *customer acquisition* path as it is about the product itself. Ask them: 'Where do you go to find information about new tools like this?'

Margin logic also comes into play. If the problem you are solving saves a company a significant annual sum, you can reasonably charge a proportionate fee. If it only saves them a small amount, you can't build a B2B business on it unless the volume is astronomical. Use the interviews to do basic calculations on your potential pricing. Illustratively, if 500 customers pay £200/month for a solution that saves them a day of work, that’s £1.2m annual revenue—not a forecast, but a way to check the scale of the opportunity.

Handling negative feedback and 'Invalidation'

Negative feedback is the most valuable data you can get. If someone tells you that your proposed solution wouldn't work for them, ask why. Their objections are the blueprint for your product development or the reason you might decide to pivot to a different segment. It is far better to discover a fatal flaw in an interview than after spending on development. The goal is to 'fail fast'—to kill the bad ideas so you can double down on the good ones.

If you encounter a complete lack of interest in the problem itself, take it seriously. It might mean the problem isn't big enough, or you are talking to the wrong segment. Don't try to 'convince' the respondent they have a problem. If they don't feel it, they won't pay for it. Move on to a different group and see if the reaction changes. A 'failed' set of interviews is actually a success—it has saved you from launching a business that nobody wanted.

Be careful not to fall into the 'I just need to explain it better' trap. If a customer doesn't 'get it' immediately, it's usually because the value proposition isn't clear enough or the problem isn't real enough for them. The best businesses solve problems that are so obvious that the customer asks when they can have it before you've even finished describing the solution.

Ethics, Data Protection, and Professionalism

When conducting interviews, you must comply with UK GDPR. This means you need a clear reason for collecting any personal data, you must tell them how it will be used, and you must keep it secure. If you are recording calls, you MUST get explicit permission before starting the recording. It's often best to use an Information Sheet that explains the purpose of your research.

Never promise a feature or a launch date during an interview. You are there to learn, not to make commitments. Manage expectations by framing the project as 'early stage research'. Also, be mindful of their time. If you promised a short session, respect that limit unless they are clearly eager to keep talking. Professionalism builds the foundation for a future sales relationship; if you respect their time now, they will respect your pitch later.