Government is formed by flawed human beings (which is perfectly fine!). It is just hard to find a lot of really smart and effective people. Additionally, most people are elected, so it's not a meritocracy.

Given all of this, you want to bound the influence of government. It's fine if we elect highly flawed humans who don't have any real qualifications; as long as they don't expand their influence frontier. This is how you keep the government functioning even when you have low quality people in office.

Interestingly, most good corporations (which actually are somewhat meritocratic as you are not hired through some democratic process) also approach this problem by limiting corporate control over the employees. The best companies out there to work for, like Google or Facebook (you can see the glassdoor list) all have a low amount of direct employee influence. This keeps them agile (nimble) to respond to an ever changing landscape while keeping the effectiveness of the employees high.

Now, the big counter to my point is that in a country you can't fire underperforming individuals whereas you can in a company and so my point is some how flawed. I don't think it is. We can take care of the poorest people in our countries without expanding the size of the government (from an employee count perspective). I actually tend to be a big fan of basic income for this reason: http://www.libertarianism.org/columns/libertarian-case-basic-income