Americans probably don't like communism, because as already stated, it has never worked out. And no body will work hard to do better, what's the point?
Also, it's common belief that, most people can do above average. Which of course, is imposable
American's don't like communism because all of us were born free. Having our freedoms taken away, being able to do what we want when we want, buying what we want, etc. are things we cannot fathom being taken away. We cannot think of being equal. Everybody is independent/different in some way, communism destroys that. Humans are not meant to think alike, we all have different opinions which is what makes us great. Genetically people want to be better than others, that's what makes the world, the world. There are people that don't want to work, thus sit at home and get paid minimum wage. Then there are those who work, and get rewarded. In communism, those two, effort or not would be equal.
Communism sucks balls, it's dumb, and hinders people. That simple.