[huehue]

It only makes sense to branch off production for hotfixes IMO.

In your example feature-B shouldn't have made it to dev.

[michaelgrafl]

Why would we need a dev branch at all then, and not just work on our local branches and merge with staging?

[huehue]

We might be discussing semantics, but try to see staging as a pre-production environment. You want to test the changes prior to deployment in an environment that is as close to production as possible, clean and accurate, while develop stays lean and dirty.

For some projects though this is a bit overkill and if you don't think this is important chances are you can get away with something more akin to the branching model rorykoehein posted.