Maybe your PR is based off a broken main branch? You can try to rebase your change on top of the latest main branch. You can also see the current status of main branch's CI at https://hud.pytorch.org/.
What are the most high risk changes?
Anything that touches build configuration is a risky area. Please avoid changing these unless you've had a discussion with the team beforehand.
Hey, a commit showed up on my branch, what's up with that?
Sometimes another community member will provide a patch or fix to your pull request or branch. This is often needed for getting CI tests to pass.