How many people should you talk to as you validate your startup idea?

Hello IH

I have been working on an in-app search & command palette service (https://magny.io), and till now I have talked to 25 people, mostly from PM and development space.

While I have gathered an enormous number of feedback and insights that would easily fill my roadmap for the next 6 months, I am trying to be cautious about what to build next.

I keep an Airtable sheet for each and every discussion, and if there is a feature request that is asked more than 3 times, then it is triggered to be a roadmap item.

My questions are - how many people have you talked to before validating / as you develop your product? What are the criteria you used to add a feature to your roadmap during those interviews?

(PS: If you also would like to receive a demo and provide your comments on a 30-min call, just let me know)