There are many problems with the government's size. Mainly, there's too many people behind each MP, people who are getting paid for helping him decide what to do and sometimes even do his job for him. Do we vote for our representatives or for their teams of secretaries and assistants. If there's 20 people working for every MP, maybe the number of MPs could be cut in half? The result would still be the same.

They aren't motivated because it's usually not their only job. In most countries MPs work part time. In the old days these jobs were given to aristocrats and it had some interesting benefits. For instance, aristocrats had a lot of money and weren't motivated by greed and much harder to bribe. You had to put really big money on the table to make them change their minds. Nowadays, when poor people suddenly come to power they can be pretty easy to "persuade". Also, aristocrats were taking politics pretty seriously, as it was their only job apart from hunting, partying and various sports and arts and were pretty well educated. These days every moron can become an MP because we have equality, which means that there has to be a member of every minority, sex, religion and even sexual preference in every group.