So they were having trouble getting money into the bank? I'd like to understand how all these startups came to use SVB in the first place and what part the VCs

So they were having trouble getting money into the bank? I'd like to understand how all these startups came to use SVB in the first place and what part the VCs played in that. I've seen people here say that they were required to bank exclusively with SVB, did the VCs encourage those terms? The story doesn't look that great if Thiel told them to put the money there before he told them to take it out all at once.