Doctor Market Fit

Doctor Market Fit

Ultimate Guide to Interviews #5: Identifying the right JTBD for your startup

How to navigate the chaotic data of interviews

Jeroen Coelen's avatar
Jeroen Coelen
Mar 04, 2026
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Chapter overview

  1. Goal: Build a customer theory

  2. Structuring and starting the interview: Keep your baby in your bag

  3. Framing the interview

  4. Don’t just ask for problems

  5. Identifying the right JTBD ⬅️ Today

  6. Understand the value in your value proposition

  7. Using the film reel technique to get detailed explanations

  8. Six techniques on how to wiggle out extra information

  9. Getting your baby out of the bag

  10. Crafting your customer theory

In constructing our theory of the customer (Chapter 1), we should understand why this customer is in the market for a solution in the first place.

The previous chapter laid out the basics of problems and jobs to be done. Consider this chapter an advanced deep dive into how to apply these ideas in your interviews.

The tactics will help you isolate the right Jobs to be Done for your startup. That’s quite important. Why?

Because if you know why customers hire your solution, the rest of your entrepreneurial journey becomes much easier, both on your problem-solution fit and GTM strategy.

To name a few, knowing your JTBD can give you:

  • Easier solution scoping: you know what is essential and what is nice to have

  • Precise segmentation: higher conversion rates when targeting

  • Tailored messaging: potential customers respond more

  • Improved positioning: customers understand you better

Sounds neat, right? Therefore, this chapter still focuses on building blocks 1-2-3 of the PMFit Logic (image below), which answers: why is this customer on the market for a solution to begin with? The JTBD is a key answer to nail.

The framework we will populate using this book.

5.1 Focus on emotional jobs to be done

JTBD-focused questions reveal the customer’s end goal. Such questions can get two types of answers: functional and emotional. Let’s see what the functional answer looks like (reiterating examples of the previous chapter).

Q (you): “What do you use Substack for?”

A (me): “To send a weekly newsletter”

That’s boring; it doesn’t provide a rich explanation of the ‘why’ behind my behaviour. Why do I do that? The other question might evoke something more.

Q (you): “If I may ask, what are you trying to achieve with your Substack?”

A (me): “To build a decent following of founders and build my personal brand”

It’s slightly more aspirational, but still, both answers are very functional jobs to be done. It’s fine to understand these, but this isn't always what primarily drives people.

It echoes what we did in the previous chapter, but we didn’t fully unpack it yet. For that, we need to focus on the emotional jobs to be done.

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