The top tier big tech companies are generally drowning in applicants, even though they are growing like crazy. IIRC, google gets several million candidates per year. They're picky because they can be.

(Things are quite different for other not-so-sexy companies that need engineering talent.)

For those who decide to go for a FAANG job - maximize your time. Prepping for an interview at one, preps you for the others, with minor differences.

So try and set up interviews with them all around the same time, while you are well practiced. Throw in a few smaller companies somewhere in there too, with different interview styles. Schedule on-sites for your least-desired opportunities first, and consider them warm ups.