In customer conversations, three types of information consistently feel like validation but are actually noise. Fitzpatrick calls these the three types of bad data: compliments, fluff, and feature requests. Each one triggers a dopamine hit ("they like it!") that makes founders and product managers feel like they are making progress — when in reality they have learned nothing. Recognizing and deflecting these three categories is the core defensive skill of customer development. If you cannot tell the difference between signal and noise in a conversation, every conversation will feel like validation.