This applies to your startup too... If your product doesn't work (either entirely or in certain edge cases), most people won't tell you about it.. they'll just

This applies to your startup too... If your product doesn't work (either entirely or in certain edge cases), most people won't tell you about it.. they'll just move on to something else. That's why it's important to develop a closer relationship with your first customers (and ideally, they're also depending on you to solve an important problem). Otherwise there's little incentive for people to go out of their way to fix an issue with a product they never got far enough along to adopt.