First of all, because it makes reviewing the code for reviewers much easier. Reviewing a messy set of random uncurated commits is really suboptimal. Second, y

First of all, because it makes reviewing the code for reviewers much easier. Reviewing a messy set of random uncurated commits is really suboptimal. Second, you might have more than one commit you want to merge to master, not just a single commit. Also rebasing is trivial and very quick once you have done some basic reading about it.