During season one of TWW in wow I unsubbed with a lot of other players because of some decisions they made in effort to push player game time retention along with general game balancing issues. I got a block where I could type whatever I wanted in it and filled it completely with the issues I saw with the game. Blizzard runs those through an algorithm and common things are addressed. I was shocked how over a half year almost all the things I filled in my block ended up fixed by the dev team and I even resubbed. So much useful info can be gleaned by exit surveys i'm amazed they don't do more with it. Its such an amazing tool to increase player retention or return.