They use vague words or buzz words. Each company they work with has a top-notch development team, has a super group of investors, and is tackling a potential 100 billion dollar market!
But the reality is, they're the number one source of unwanted email in my inbox (sometimes even my work inbox). They spam hundreds of developers and get 30k when ONE ends up in a hire. So, kill the body, the head will die. If no one works with 3rd party recruiters, companies will stop hiring them. And the email will go away!
As a signer of this pledge, the next time you get an unwanted 3rd party recruiting email, please: