It is quite clear that there aren't much people (or any at all) which aren't registered but want to because if they want, there aren't much reasons why they have not already.

While there might be more reasons about the mirrored case, i.e. you are registered but want to leave but have not already, I wonder what these are. It isn't really complicated to do. Maybe it is just more like 'I would leave if there would be a better alternative but otherwise I'll stay`? Or just 'I'm not sure yet'?