This document discusses the importance of surveying and interviewing customers to gain insights and test assumptions. It provides the following key points: 1. Surveying and interviewing customers is important to avoid building products based on incorrect assumptions about what customers want. Asking customers questions can help validate or invalidate assumptions. 2. Great customer surveys involve asking insightful questions in the right way. The questions should provide learning around pricing, what to launch first, who to target initially, and how to engage early users. 3. Common assumptions that should be tested include whether customers will download an app, subscribe to a service, or that building the right product alone will attract customers. 4. Suggested ways