[JohnFen]

> And most modern interview processes do not give you credit for thinking through it. You only get through if you solve it the right way, and fast.

Interview processes that do it that way are fundamentally broken. I wouldn't want to work at such a company. Interviews are two-way streets, and that would be a case of the company failing the interview.

The real benefit of this sort of interview practice is not learning whether or not the candidate can arrive at the correct answer. If we're at the point where this level of interview is even happening at all, you have (or should have) reasonable confidence that the candidate is capable of solving the problem. Whether or not that they do so in the interview is irrelevant. The real benefit is in being able to see how the candidate thinks through the problem.

While I think these whiteboard exercises are not the best approach, when I've been the interviewer at companies that required it, I chose a very difficult problem, gave a time limit, and told the candidate that I do not expect them to actually arrive at the solution within the given time. I just want to see how they approach the problem.