"because the people want them to" is a bit of an oversimplification to say the least. The people, influenced by media, various factions and their own interest,

"because the people want them to" is a bit of an oversimplification to say the least. The people, influenced by media, various factions and their own interest, vote for people who then may or may not do things that "the people want", because they operate within a particular context, zeitgeist, resistance to change, optics, party dynamics, outside money and what they perceive the people to want.