Because most people do a really bad job at technical interviewing and selection - there's so much to say about why it would take a book to explain it all. BUT importantly - everyone thinks they do a great job at interviewing and selection.

>> As a recruiter what percentage of the time are you throwing candidates at jobs to see what sticks?

I'm not sure I understand the question. Is it saying "recruiters send any old person for a job in the random hope they might get it, how often do you do that?".

I don't do that.

I try to find the right person for the job, I look for people who are smart and get stuff done and I send people who I think are going to contribute something meaningful to a company. I use my technical expertise to try to understand the candidates level of technical experience, and I articulate the strengths and weaknesses of the candidate to the employer.