Back when I used to hire programmers (c 1990-2000) for a computer games company I used to run, we used to do a programming test during the interview and this weeded out a lot of people who claimed competence but really had none.
(My favourite example was someone who had written ‘Assembly language programming’ on their CV but didn’t know how to answer the question ‘for what processor?’ in the interview. Also, I interviewed someone once who, when asked what their hobbies were, replied “I smoke a lot”)
But what really astonished me was the level of BS on people’s CVs. People claimed to have written famous hit games when they had not (we knew the people who actually did write them) or people who claimed to have worked for MI5, the CIA or Mossad. If they had worked for these organisations they wouldn’t say so on their CV. If only out of self-preservation, never mind the Official Secrets Act. This made me think that a lot of the stuff on CVs that was harder to disprove was also BS.
In the words of Ronald Reagan: “Trust but verify!”