Exactly this, plus high pay. However, I've known lots of people who have worked at FAANG companies and while they tend to hire extremely bright people that does

Exactly this, plus high pay. However, I've known lots of people who have worked at FAANG companies and while they tend to hire extremely bright people that doesn't correlate with everyone doing interesting work. As a friend put it, "yeah, I got to work at Google but I spent 3 years fixing obscure bugs in the Dart engine for Chrome." Also, keep in mind that the FAANG companies sort of have to pay a ton because most engineers would likely rather work at a startup where they get to be big fish in a small pond and build something new.