Important: same goes for bonuses, which are also practically promises, and are not guaranteed.
[1] https://twitter.com/ed_solomon/status/1139031900931198976
Is there a clause for when an upstream team decides to stonewall the work you've involved with?
What happens when your boss transfers and the new person you report to doesn't have any history to go on?
This stuff happens all the time, although mostly at the business level. Zeroing it out is a great way to make sure you aren't in financial position where you're taking a risk on things you don't 100% control.