Most tests are essentially nothing more than tests for the ability of rote memorization - they don't (really) check if the students actually understood the material and are able to apply it to new situations ("transfer of learning"), especially because it is way more difficult to create such tests and to fairly grade them. However, rote memorization tests are extremely easy to cheat on, which requires intrusive countermeasures.
In the end, this is a "common thread" across most of modern academia - the focus has long since shifted from taking in the most gifted of society for actual academic research to providing a fresh herd of fungible graduates for large corporations to prey upon each year, and it shows everywhere from how admissions are handled over the sad and sorry state of frontal teaching to, as seen, dehumanizing exams.
ETA: I've ranted about the causes in the past here, with the reply to my post being really worth the read IMO: https://news.ycombinator.com/item?id=32383965