Why do people actually believe that socialism/communism doesnt work?

Are people just ignorant to the fact that communism and socialism do work. Look at Russia which is emerging economically speaking and go to China a see the progress going on. Look at Sweden which is a rich socialist country and venezuela which has one of the highes per capita in latin america. OPEN YOUR EYES!!! Communism doesnt work when there is corruption, so dont get me wrong, just like cuba.