When a programmer goes through a question fast and jumps right into the solution, there is two possibilities. One is candidate already knows the question. Two is candidate is exceptional programmer. If the other part of the interview doesn't match up to this, then we will assume the first case.
I definitely place candidates who are being honest upfront above others. They will be reliable and trustworthy, which is important quality for programmers.
First principle that every interview guide teaches you is to take time to understand the questions. A candidate who has spent months preparing for a FAANG interview will highly unlikely rush into answering a question, even if they have seen the question before.
One reason for folks to jump right into the solution is the interview anxiety - which is both due to lack of practice and trying to compare oneself to folks preparing for months ahead of interviews.
When a programmer goes through a question fast and jumps right into the solution, there is two possibilities. One is candidate already knows the question. Two is candidate is exceptional programmer. If the other part of the interview doesn't match up to this, then we will assume the first case.
I definitely place candidates who are being honest upfront above others. They will be reliable and trustworthy, which is important quality for programmers.