Only half of the people who viewed my game have downloaded it and from that only half of them have rated my game.
It is completely normal that not all views or downloads result in a rating.
As already mentioned in this thread outsiders decide to click on your game or download it. On the other hand you have people like me that check the games page notice that it has no executables compatible with my system and leave. I sometimes even download a file to try it with wine or mono, but it rarely runs.