Because we do silly testing, social tests, and many more test instead of trusting the good old "hire a smart guy by gut feeling + probe (not test) the extend of

Because we do silly testing, social tests, and many more test instead of trusting the good old "hire a smart guy by gut feeling + probe (not test) the extend of his knowledge" method. I am a person who does interviews and I always use this method. Never betrayed me.