Because the people doing the recruiting seldom have the training to tell who's a good candidate or not. Software creation is an art, not a science, and finding

Because the people doing the recruiting seldom have the training to tell who's a good candidate or not. Software creation is an art, not a science, and finding a good developer requires understanding his knowledge of the technology as well as his approach to problem solving. There's never only one right way, so it's hard to create a standardized test that non-devs can use for screening. Also, it's a numbers game. They just want to throw bodies at you and hope something sticks. Turns out quotas and commission are the enemies of quality.