It's my crude estimate based on the places I've worked over the years, and the people I've seen come in when my employers were interviewing. If I was the boss

It's my crude estimate based on the places I've worked over the years, and the people I've seen come in when my employers were interviewing. If I was the boss and had a "toxic" employee, I'd just dump them rather than waiting. I've been forced to work with toxic people because I'm not the boss, and I've noticed that toxic people are really good at pretending to be brilliant. Over the years, I've also worked with a couple of people who singlehandedly wrote all of the employer's key software. I also worked with several people who wrote a garbage system but conned everyone else into thinking it was brilliant. If 90% of candidates are "good", then why waste time with a detailed technical screening at all? Just interview a couple and pick the ones you like the best.