I actually don't think this is true. My understanding is if you're PIPed they don't really care. The signing bonus is paid out monthly the 2nd year (and for people hired at SDE2+ its first year too) so you don't have to pay it back after the first year.
Disclaimer: Amazon L4
Part one is in your first year where you get a lump sum signing bonus with your first paycheck (paid monthly) with the understanding that if you leave you would pay back a pro-rated amount proportional to how many months were left in the year.
Part two is in your second year and is paid partially with every pay check and if you leave you don’t pay anything back, you just don’t get the remainder of the money to be paid out the rest of the year.
After year two stock vests tend to vastly outpace the signing bonus pay but I’d imagine this varies on the stock price.
I've interviewed at Amazon and had a lot of conversations about compensation. I don't know about the terms of the relocation bonus, but for the signing bonus, you don't pay it back if you are fired and even if you leave voluntarily, you only pay back a pro-rated amount. For example if your signing bonus is $20k, and you leave at the 6 months mark, you owe $10k back but you get to keep the other $10k.
When I graduated college, all of my friend group discussed it and we all took out a small chunk of the bonus to go on a small group vacation, but the rest of the bonus got put into an investment account and not touched for at least a year. That way if we did decide to leave, the money was easily accessible to be paid back. I know not everyone has that flexibility, but it's probably the best way to approach signing bonuses if you're not 100% sure you will be at the company long term.
also, anecdotally, it you were fired they would not ask for the bonus back - it opened a whole can of worms in the wrongful termination bucket
so op definitely did not read his employment contract
Paying back a signing bonus if they fire you seems super rough. Is this common elsewhere? 2 years also seems high - the time I got a signing bonus, it was "pay back if you leave voluntarily in 1 year" which was much nicer than the described.
Unfortunately, much of this seems pretty common, especially months-of-crunch-time. Being able to figure out projects to avoid (if you're at a big corp like this where such things are possible), and being able to avoid them is a very good career skill to cultivate.
On-call can work quite well if the team has sufficient ownership to improve the underlying issues, not just keep the lights on. I've done this with good success. I'm often disappointed by how many managers and companies I've seen who don't get that aspect.
Believing too much in mantras like "adding manpower to a late software project makes it later" can be dangerous, too, though. How well it works depends on the manager and the person scoping and planning the work. Another critical skill to develop to escape being the person doing the grunt work.