Hopefully you have researched the place before - if not, RIP latest now. However, its also closely related to the company culture. If its run by bureaucrats afraid of change, to say that you want to modify or introduce new things would probably seal your fate right now. Again, its tricky because at this stage you probably dont know that. My advice is irredgardless to say what you really would like to do. If its a fit, congrats. If not - you are better off not changing to that place anyway.
If thats asked by the boss, obviously you want his/her job. Obviously also, you should not say this. Especially not in a German environment. So you say that you want to work for a company whom you helped to double the turnover/revenue etc etc.