[redspark]

When we are coaching companies through the problem interview stages we set some basic ground-rules.

Interview at least 30 target customers. Anyone who doesn't fit into your pre-determined persona doesn't count.

Set the success/failure criteria before the interviews. For instance, we are going to talk to 30 potential customers and we are going to focus our questions about a pain point in this particular area. Of those 30, 21 will agree they have felt pain when dealing with this area.

Typical number of questions is 10, mostly to qualify them as fitting in the demographic. Take notes mentally, but not during the interview (taking notes during the interview infers a test and they will try harder to get the "right" answer). Immediately after the interview, document the interview. Make sure to allow the interviewee to elaborate on any question, as they may reveal other areas with pain. If they admit pain in the area you are targeting, ask them what they are currently doing (your biggest competitor may be that they aren't doing anything). Then subtly try to talk them out of the problem being a pain. If you can't talk them out of it, it is indeed a pain point they want solved.

Once you have 30 look at your interview summaries, determine if you have validated or invalidated the assumption. If invalidated, really look close at the responses you did get, since they will reveal other problems to explore.

[nayefc]

Make sure you do not steer them into answering your questions; but let them come up with the pain/conclusions on their own.