[maw]

Chances are they're pushing to the same branch or to the same small number of branches instead of to private-ish branches. This is an easy trap to fall into: lots of people have a hard time getting used to using branches for everything.

As for squashing or not, I rarely do, and in general only squash commits that are simple typo fixes. This makes bisecting much easier.

Also, and this may or may not be relevant, maybe some people are reluctant to spam the central repository with their own temporary branches. To avoid this, I have everyone in my team set up a personal, backed up repository. Anyone can pull from these personal repos, but only their owners can push to them. When the temporary branches are done, they can be merged.