Fairness is definitely not relevant here. But, an interview technique can be useful for a company or not. Asking candidates to write code on the spot isn't inh

Fairness is definitely not relevant here. But, an interview technique can be useful for a company or not. Asking candidates to write code on the spot isn't inherently useful or not useful. Assessing a candidates typos and compiler errors smugly is probably not very useful. But assessing their approach to understanding expectations, understanding problems, and solving problems is useful. If a candidate just assumes the expectations without asking in the interview, they are likely to do the same on the job.