But that's how parliament works (well, ought to work, anyway). This isn't East Germany. They're not there to rubberstamp everything the government wants to do, they're there to oversee it. And if the majority of them think the government is not doing its job properly, then they're perfectly entitled to vote it down, in which case the leader of the opposition is next in line to have a go. It's got nothing to do with being a power-crazed idiot. Those are the rules.
Not that anything like that is likely to happen anyway, given that most parliamentarians are craven pole-climbing swines that are desperate to stay there come what may.
But that's the theory, at least.