[getsat]

Because it's awesome to alter history and push your changes when working with other people! Yay!

[zrail]

This is why people don't like rebase, but if you just tell people "never start a rebase farther back than master" the problem magically goes away. Tada!

[masklinn]

It's even simpler and more general than this: don't rewrite public history. There, you're done.

[gruseom]

I'd add that it's only a problem as team size grows. If the only other people who might be affected are sitting nearby, I can say "has anyone pushed since <commit>" and happily push -f my rebase in most cases.