Not necessarily. Anyone who has had an app on the store knows that there are lots of reviews that are simply inaccurate. If unhappy users would contact the devs first, many "problems" can be easily solved.

For example, many people don't understand lots of apple's UI decisions that we take for granted. I had a user contact me and ask if our app did X. It does, I told him that, and he bought the app. Then I got an angry email saying it doesn't do that. (the thing was persisting data when "closing" the app with fast app switching.)

Well he thought all his apps were running constantly in the background draining battery so he force closed everything when he quit them. Obviously my app can't do the fast app switching persistant data if he force closes it. In no way does my app deserve an angry 1 star review when a simple email explanation can fix the problem.