Why git commits don't contain the name of the branch they were created on?

Just a design decision. If you need that information, you may add a prepare-commit-msg or commit-msg hook to enforce that on a single repository.

After the BitKeeper desaster Linus Torvalds developed git to match the Linux kernel development process. There, until a patch is accepted, it is revised, edited, polished several times (all through Mail), signed-off (=editing a commit), cherry-picked, wandering to branches of lieutenant maybe often rebased, more edits, cherry-picks and so on until they a finally merged upstream by Linus. In such a workflow there may be no specific origin of a commit, and often a commit is just created in some temporary debugging branch in some unimportant private random repository with funny branch names, as git is distributed.

Maybe that design decision just happened coincidental, but it exactly matches the Linux kernel development process.

Why git commits don't contain the name of the branch they were created on?

Just a design decision. If you need that information, you may add a prepare-commit-msg or commit-msg hook to enforce that on a single repository.

After the BitKeeper disaster Linus Torvalds developed git to match the Linux kernel development process. There, until a patch is accepted, it is revised, edited, polished several times (all through Mail), signed-off (=editing a commit), cherry-picked, wandering to branches of lieutenant maybe often rebased, more edits, cherry-picks and so on until they a finally merged upstream by Linus. 

In such a workflow there may be no specific origin of a commit, and often a commit is just created in some temporary debugging branch in some unimportant private random repository with funny branch names, as git is distributed.

Maybe that design decision just happened coincidentally, but it exactly matches the Linux kernel development process.

Why git commits don't contain the name of the branch they were created on?

Just a design decision. If you need that information, you may add a prepare-commit-msg or commit-msg hook to enforce that on a single repository.

After the BitKeeper desaster Linus Torvalds developed git to match the Linux kernel development process. There, until a patch is accepted, it is revised, edited, polished several times (all through Mail), signed-off (=editing a commit), cherry-picked, wandering to branches of lieutenant maybe often rebased, more edits, cherry-picks and so on until they a finally merged upstream by Linus. In such a workflow there may be no specific origin of a commit, and often a commit is just created in some temporary debugging branch in some unimportant private random repository with funny branch names, as git is distributed.

Maybe this design decision just happend coincidental, but it exactly matches the Linux kernel development process.

Why git commits don't contain the name of the branch they were created on?

Just a design decision. If you need that information, you may add a prepare-commit-msg or commit-msg hook to enforce that on a single repository.

After the BitKeeper desaster Linus Torvalds developed git to match the Linux kernel development process. There, until a patch is accepted, it is revised, edited, polished several times (all through Mail), signed-off (=editing a commit), cherry-picked, wandering to branches of lieutenant maybe often rebased, more edits, cherry-picks and so on until they a finally merged upstream by Linus. In such a workflow there may be no specific origin of a commit, and often a commit is just created in some temporary debugging branch in some unimportant private random repository with funny branch names, as git is distributed.

Maybe that design decision just happened coincidental, but it exactly matches the Linux kernel development process.