"Changing it from the inside" is a carrot dangled in front of people to make them think that they can effect change by becoming a cog in the machine. First off, cogs don't change the machine specifically because they're limited in their function.
The people who join the government to try to change it from the inside are the same people who, five years later, complain that their hands are tied and they can't effect meaningful change for the better and must continue along the well-trodden path of obedience. I think Obama is a great example here, but I'm sure there are many others.
The only possible way to change a government is from the inside. Even if you have a violent revolution, what happens next? The leaders of the revolt become the leaders on the inside of the new government.
Government is not like a company you can boycott; it is an unavoidable attribute of human society. The operative questions are how are you participating in it to achieve your aims, and how effectively.
The people who join the government to try to change it from the inside are the same people who, five years later, complain that their hands are tied and they can't effect meaningful change for the better and must continue along the well-trodden path of obedience. I think Obama is a great example here, but I'm sure there are many others.