When you say "test" are you referring to technical coding challenges in the interview process? An interview is essentially a test, regardless of whether it contains a whiteboard coding assignment, a presentation, or even just a conversation. At the end of the day an interview is designed for a company to decide whether or not they should extend an offer to a candidate and (hopefully) for a candidate to learn about the company before potentially accepting an offer. The point of this process is for both parties to decide if they would be a good fit together. They are literally "testing" each other.