Short-term ministers

In The FT Steve Bundred, chief executive of the Audit Commission, questions whether it is possible to have strong and effective Government when ministers rarely last long in any one post.
The revolving door policy works for Premiership managers, to a degree, but is it any way to run a country?
It also brings up one of the inherent failings of our democratic system. Politicians are there to get voted back in, not worry about what the country will be like in 10-15 years' time when they are cashing in on pensions, directorships and cash from memoir royalties