3 Common Customer Interviewing Mistakes

10 Good Interviews > 100 Mediocre Interviews

At the early stages of a product, customer interviews are the best (and fastest) way to learn from customers. Many incubators and accelerators even pay or withhold follow-on funding from founders until they conduct a hundred customer interviews!

While I get the intent, I’m not a fan of this approach.

First, simply talking to a hundred people doesn’t automatically lead to breakthrough insights.

Second, when you focus on quality instead of quantity, you often need just 10-20 interviews to extract all the key insights in any study.

Knowing how to run good interviews is important; knowing who to interview is even more important.

The secret to running good customer discovery interviews starts with good prospecting.

In today's issue, I will lay out the most common prospecting misconceptions and show you what to do instead to improve the quality of your interviews.


Misconception #1: Targeting early adopters

Homing in on your ideal early adopter criteria is an output of customer discovery, not an input. Prematurely targeting your definition of early adopters could do more harm than good.

Here’s why.

Most early adopter criteria start as best guesses. The danger with relying on them is going too narrow, finding validation, and falling into a local maxima trap, i.e., chasing too small a market.

Example: If I define startup founders using the old stereotype of two guys in a garage in Silicon Valley, I’ll find them but miss the mountain of founders worldwide.

Ironically, falling into a local maximum is worse than finding invalidation because it’s a false positive that leads to spending needless time, money, and effort on the wrong market.

What to do instead:

Run two phases of problem discovery interviews:

  • Broad-match to map the overall market opportunity and identify your ideal early adopter criteria.
  • Narrow-match on early adopters to uncover problems worth solving.

Misconception #2: Targeting a specific job-to-be-done

If you’re familiar with the theory of jobs-to-be-done, you might be tempted to come up with specific jobs your product does and try to use them in your targeting criteria.

The most insightful jobs, however, are like magic tricks. They are obvious in hindsight but hidden in foresight. They, too, are outputs of the customer discovery process, not inputs.

Example: In the famous milkshake study, the researchers discovered the unexpected job of the milkshake through the interviewing process. They didn’t guess at the job, but instead asked why anyone would be buying a milkshake at 8 am in the morning.

What to do instead:

  • Use a starting job scope (typically a functional job tied to needs) to contextualize your product domain to identify direct or indirect existing alternatives (this is what you target).
  • Use broad-match discovery to discover and rank the bigger context jobs (typically emotional jobs tied to wants).
  • Use narrow-match discovery to home in on a specific job.

Misconception #3: Targeting active buyers

The most common pitfall, by far, is targeting potential customers of your product, aka active buyers. While building a pipeline of qualified prospects as a byproduct of customer interviews is tempting, active buyers don’t make for good interview candidates because they haven’t bought yet and maybe never will.

Happy customers are alike; each unhappy customer is unhappy in their own way.
- Adapted from the Anna Karenina principle

This last insight is the key to shrinking the number of interviews needed for problem discovery.

For any given product, there aren’t dozens of reasons people buy (or hire) them. But there can be dozens of reasons why they don’t.

The most actionable insights come from customers who have successfully hired and used a product (existing alternative), not active buyers still looking.

Golden rule of problem discovery: Measure what customers did, not what they say they’ll do.

Example: If you’re a home builder, the best people to interview are people who just bought a home, even though they are the worst people to sell your houses to.

What to do instead:

Only interview people who have recently attempted the job or, more specifically, recently used or consumed one of your existing alternatives under study.

Putting it all together

Your objective is modeling after successful customers who took action (hired an existing alternative), not unsuccessful prospects still looking.

Here’s how to frame your initial targeting:

  • Prospecting Criteria #1: Target prospects based on how recently they switched (or used) a direct existing alternative.
  • Prospecting Criteria #2: Target prospects based on how recently they switched (or used) an indirect or complementary alternative.

Through these interviews, you

  1. Uncover and rank the non-obvious bigger context jobs people are trying to do (Broad-match problem discovery)
  2. Home in on a specific job worth winning to uncover problems worth solving with the old way (Narrow-match problem discovery)
  3. Design a solution to cause a switch from the old way to your new way
  4. Sell your solution before you build it using a mafia offer.

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