Not nearly as badly. A badly done merge can indeed ruin code. But you'll always have the versions that went into the merge, and the merge itself. Your history

Not nearly as badly. A badly done merge can indeed ruin code. But you'll always have the versions that went into the merge, and the merge itself. Your history has all of the information to recreate exactly what happened, find what changed, and then figure out how to fix it. A badly done rebase not only ruins your work, it also removes from the branch any record of your work having been done. Unless you can find the right stray old commit which is not yet cleaned up, there is no choice but to start doing it again from scratch.