While I broadly agree: data lies too. "X% more people use this now" says absolutely nothing about if they like it, or if it's doing what they want, or if you'll drive them off the system in a couple months because of it. It just says that X% more used it during the time you were watching.

You can use nothing but positive data-driven results to drive yourself out of existence, and it's rather easy. Direct, human feedback is absolutely essential.