Outside of development there are very few jobs that have a competency test as part of the hiring process. Some industries have "continuous testing" through certification, and some have tests of things like physical fitness, but in general it's assumed that if you're applying for a role then you're capable of doing it. The economy isn't collapsing under the weight of corporations hiring the wrong people all the time.

I suspect there are technical tests in developer interviews because there can be rather than because they're actually a useful way to appraise someone.