The conversation that gets the truth

People are generous. Asked whether they would use a thing you clearly care about, most will say yes, because saying no to an enthusiastic person is unpleasant and costs them nothing. That yes is worthless and it is the most common piece of evidence in a failed venture.

The fix is mechanical. Ask only about the past, because the past already happened and cannot be adjusted to be kind to you. "When did you last run into this?" "What did you do about it?" "What did that cost you — money, hours, or a customer?" "What else did you try before that?" "Who else was involved?" Every one of those has a factual answer. "Would you use this?" and "Would you pay for it?" do not.

Two moves make the rest easier. Do not describe your idea until the end, because once they know what you want to hear they will help you hear it. And when someone praises the idea, treat the praise as a signal to dig, not to stop: "That is kind — what are you doing about it at the moment?" often turns a compliment into an admission that they are doing nothing, which tells you the problem is not painful enough to act on.