When we vote for a local MP the idea is that we vote not just on the individual issues we agree on with them but that they are able to understand and inform on constant issues that arise.
Have you ever spoken to MPs? In the Government Department I worked in, I did so on many occasions in the Management grade I was in. Couldn't believe the lack of basic understanding of simple issues from most of them (I will not reveal names on a public forum), and for the more complicated issues, forget about it.
If you think it's MPs who work through complicated issues and bring them to fruition, think again. It's senior civil servants. Why do you think MPs never answer the questions put to them when they are interviewed on TV? Either they're too thick to provide a cogent answer, or too cunning to reveal what they really think. WHen the 'Minister for X' stands up in Parliament to hold forth on a particular issue, that has been prepared and written for him by his staff of civil servants. 'Yes Minister' & 'Yes Prime Minister' are way closer than people realise...
The only two MPs I've ever had time for are Dennis Skinner and Jack Ashley.