The entire political system in the U.K. is totally flawed and it is impossible to beleive that the most powerful empire in the world at one point still can't sort out its issues with electoral reform.
There you have to see how many overall districts out of 651 you can win but you only ever vote for your local MP who is affiliated (usually) to a party but if you support your local MP who happens to be a part of the national government who you don't support then you're screwed! To vote out the leader in Westminster you would need to vote for a candidate that was in a different party to his in your own local district irrelevant of the performance of the local MP who was affiliated with the same party as that of the leader.
Its total nonsense and about time there was some reform in Britain.