I could answer, but I don't think you're actually asking for someone to explain it to you.
I did want to offer a different opinion though. I like detached heads, they are unnamed branches, the first thing I do when working on something new is make a detached head and get to work, making commits, etc, if I decide the work is worth keeping, then I will name the branch. As some smart people have said, naming things is hard, I don't want to name a branch before I'm sure what it is or that I'm going to keep it. Having a bunch of commits that are not part of a branch might sound risky, but not if you understand that commits are never deleted (unless there 90 days old or more) and the reflog and other tools allow you to find commits you thought might be lost. Git does not lose commits, not ever.