What is the difference between High Score and Perfect Score?

This one says it well ---

"高分和满分有本质区别。满分不但要聪明，除了知识过硬外，心理素质的从容自如、应试（处理事情）技巧的细心周到，等等，还需详细全面地融会贯通，干什么都一做就对，给人以满分的上限有无穷想象"