My last airline had a pretty good recruitment system in which someone with some knowledge or experience in parallel with the applicant was "co-opted" onto the selection process (interview, simulator or "lunch-time tea and sandwiches").
I was able to spot a couple of imposters..........one because he kept referring to his time on "one-two-oh squadron...........(always known as one-twenty) and the other because the aircraft on which he claimed 1000 hours hadn't been introduced in that period. Closer examination of their CVs showed an imaginative but fictional background.
Nowadays the recruitment process tends to be conducted by an army of HR people with personality, compatibility and PC tests without the "gut-feeling" that warns a professional airman that something is amiss with this particular chap ?