Comment by wat10000

The first half of the title is correct, the second half is obviously wrong.

Take someone who is absolutely calm under pressure (an astronaut, say), but who has never so much as seen a line of code, and give them a live coding exercise. They’re going to fail completely.

They measure coding skills and ability to function under stress. If you’re looking for coding skills, it’s a useful albeit imperfect proxy. And you may well be interested in performance under stress too.