It just takes time and patience to get the sort of political capital that you need to make change. You wait for disasters to happen because of incompetence and then you pounce. There's also a finesse to it though, half of the battle is convincing the right people that they had these ideas in the first place. I also employ the "whisper campaign" often. Just seeding ideas in various conversations lightly, once people start to say them in conversations without you prompting it you know your job is done.