Metrics are really good, and really can help you reason about what will happen to usage when you add, remove or change a feature. There are two better / essenti

Metrics are really good, and really can help you reason about what will happen to usage when you add, remove or change a feature. There are two better / essential tools: First, dog food / use your product if you can. I build recruiting software. When I hire developers, I am a user, just like my customers. You'll really feel the impact of defects and bad assumptions have, and it will really help you understand how to make users happy. The second is to work closely with a few customers. This way you have someone who can heat check the metrics and confirm they are having the same experience you do when you dog food, to make sure you are not being led to an alternate reality.