In my experience, it's like being sabotaged. If one has a previous interest in the subject but is forced to complete all the same courses it gets very very tedious. Akin to being forced to fill middle school worksheets - you can do it, but it takes time and is just mind-numbing.
I think US universities are forced to cover things again due to a failure in the K-12 system of schooling that precedes it, and the lack of adequate testing to weed out ill prepared individuals.
In many countries, these kids would probably not get into college in the first place due to failing preparatory tests. In the US there are many financial incentives to pull in as many kids as possible and that may cause a lowering of barriers.
An observation in the maths, many countries in Asia cover calculus at the middle school level and continue into high school, in the US I noticed many public schools categorize calculus as an advanced (sometimes elective) high school subject.
