> They could just ignore leetcode and ask puzzle problems instead to test ability.
One of the hiring fads before leetcode was to ask puzzle questions, with a heavy emphasis on Fermi questions and trick questions. These had the same failure modes.
It turns out that hiring is hard, involves some risk, and always tends to illustrate Goodhart's Law: whatever process you put in place to avoid that risk will ultimately become worthless when people start optimizing for it.
One of the hiring fads before leetcode was to ask puzzle questions, with a heavy emphasis on Fermi questions and trick questions. These had the same failure modes.
It turns out that hiring is hard, involves some risk, and always tends to illustrate Goodhart's Law: whatever process you put in place to avoid that risk will ultimately become worthless when people start optimizing for it.