Whether you’re a startup or part of a larger product team, interviews with prospective customers are the best way to test your assumptions and identify problems worth solving. If you are actively developing a product and have yet to get out of the building to validate your assumptions, how do you know you’re on the right track?

In 10 Tips for Amazing Customer Development Interview (Part 1) I shared the first five ways to get the most insight from each conversation. Here are five more.

Tip 6. Tell them what their problems are. That’s right – you tell them. Present them with a list of problems you have heard from others (or problems you think they have). Your primary goal is to identify repeatable problems worth solving, and if your customer doesn’t share the problems on your list you may be on the wrong path.

Ask them if they agree or disagree with each item in your list and to add other problems they have experienced. If they agree with a problem, ask for specific examples. Then ask them to prioritize the top problems. If you can, find out the cost of the biggest problem (whether it’s lost time, lost money, lost opportunity, and so on). You can replay this insight later in the interview to help justify the return on investment for your product.

Tip 7. Ask difficult questions. Asking difficult questions may make you a bit uncomfortable, but will elicit insight you might not expect. For example, if the customer tells you what their biggest challenge is, ask: “How much is it worth to you if we solved that problem?”

Or if the interview isn’t going anywhere, take a cue from the theory of “reverse selling” and state “Based on what you’ve been saying our product doesn’t sound like a good fit for you – am I missing anything?” Of course all of this needs to be done with tact and stated in a nice way to avoid sounding like a jerk.

Tip 8. Ask if they’ll buy. This tip may not be relevant if you are in the early stages of customer discovery where you are attempting to identify problems. However, if you are further along in the process and have a product hypothesis, get this question on the table early – you do not need to have specific pricing to learn a lot. Ask something like “If this were available today would you buy it?” Then take a deep breath and let them talk through their rationale.

If they say, “yes,” here is where your job gets hard. My core principle is that people like to help. But that means they may give you answers you want to hear. So here is where Tip 5: Dig Deep comes into play: You need to ask them to justify their answer. Ask them “why.” Ask them how much they would pay. Ask them what their world looks like after they buy your product.

Challenge them (nicely) with your questions and you will gain a ton of insight – and a potential early customer. I have conducted a number of interviews where the prospect thought through the purchase process and were a probable buyer by the end of the discussion.

Tip 9. Ask for a referral. Over the years I’ve learned that my best source of prospects is through existing contacts. While cold-calling and other methods are great ways to test your acquisition model and sales funnel, the rate of success is much lower than a warm referral. At the end of the interview make sure to ask “Is there anyone else we should talk with?” or “Would you mind introducing us to a peer of yours at a different company?” If they are willing to make an introduction via email, offer to send them boilerplate text they can use when making the introduction – this will make it easier for them to follow through.

Tip 10. Leave on great terms. Don’t overstay your welcome, but know that people will give you time if you are respectful. Practice good time management. If you said you would spend 30 minutes, ask for permission to continue at the 30-minute mark. Chances are they will give you more time.

You want to leave on great terms, because at the end of the interview you want permission to contact them again when your hypothesis is further along. Oh, and follow up with a thank you email. That may seem obvious, but I’m always surprised at how many people don’t do this after an interview.

Customer development requires critical thinking and challenging all your assumptions. Great interviews with prospective customers are absolutely best way to have higher confidence your product is on the right track.

When it comes to discovering and validating a great product, nothing is a substitute for hearing the good, bad, and ugly first-hand from potential customers. The interview is the most basic, core part of customer development, and is the best way to challenge your assumptions, validate your minimum viable product, and find early customers.

If you’ve done even a handful of customer development interviews, you know what a great interview feels like. The energy is high. There is synchronicity with the potential customer. Even if you don’t get to “yes” at the end of the interview, it can be a fantastic and rewarding experience because you have learned something new. That’s the point, right? You have gotten one step closer to validating your hypothesis.

After conducting over 1,000 interviews for startup products that did not yet exist I’ve developed a handful of techniques for getting the most insightful data out of your precious time with potential customers. Although most of my experience is with Web-based business software, many of these same concepts hold true with consumer software and other products. Here are the first five tips for conducting an amazing interview.

Tip 1: Interview the decision-maker. For consumer products, this is often straightforward. However, if you are pitching a proposed solution for a business, make sure you are talking with the person who writes the check or has significant influence over the decision. Sure, interviewing users is an essential part of development, but at this stage, you are trying to determine if someone has pain, which in turn leads to whether they will buy your product. If you are early in the customer discovery process and do not yet know who the buyer is, start with the person you think has the biggest problem, and ask them to walk you through the steps of a hypothetical purchase in their organization. They will lead you to the person with buying authority.

Tip 2: Prepare your questions – but don’t follow a script. This should be a conversation, not a structured interview. But since you are testing a hypothesis, be sure to write down the questions in advance so you know what to ask to prove your ideas. It will also help you stay on track and get the most out of the customer’s time. Feel free to deviate from the script though and don’t stress about getting an answer to everything – you will learn more by letting the conversation flow naturally. Don’t bother to send questions in advance to the customer; you should be listening closely to their reaction. Another tip: ahead of your interviews write down what you think the answers will be. It’s virtually guaranteed that you will hear something different from customers along the way and it’s a great way to document your learning.

Tip 3: Ask open-ended questions. In the early discovery stages you don’t know the right questions to ask, so open-ended questions lead you to new questions you hadn’t thought of asking. If you are asking Yes/No questions in your interviews, you are assuming too much. Open-ended questions give you insight into desires and motivations that can help you understand buying behavior (often an irrational process). Asking a customer “what’s the worst part of your day?” will yield far more insight than several survey-type questions. Yes/No questions are fine for getting specific answers, but they presume you know the right questions to ask.

Tip 4: Let them talk. You should be talking less than half the time. Ask them a question and then shut up. It’s OK to let a potential customer think about their answer. Let customers fumble through their answers without jumping in and you will get deeper insight into their thought process. It’s OK to have a bit of radio silence. If you are at the early stages of your product concept you should be in pain-finding mode – when you let customers speak, you may find pain in unexpected places.

Tip 5: Dig deep and ask why. Don’t accept the first answer and move on to the next question on your list. Use the five whys to get to the root cause of a statement. During discovery for a new product a few years ago, I had potential customers tell me they hated going to the office on the weekend to finish up work. Taken at face-value, this is obvious –who loves going into the office on the weekend? But by probing deeper, we uncovered underlying fears and desires. They wanted to see their kid’s soccer match. They feared missing a potential business opportunity. They wanted flexibility. Through deeply understanding customer problems and our value proposition, we were able to build the right features, charge a higher price for the product,and craft better messaging. By asking “why?” you can understand real motivation and uncover your product’s potential.

In the next post I’ll share five more tips for getting the most out of your customer development interviews.

10 Tips for Amazing Customer Development Interviews (Part 2)