The thing is, just talking about it as a device out of context, it can't help but feel contrived. It's the wrong way of approaching the question. You don't start with a device and then concoct an excuse for using it. You start with the story and use whatever storytelling mode works for it. If the story needs to be told in alternating first-person chapters headed by the characters' names, then it wouldn't feel awkward (probably). Otherwise, it just feels like an imposition.
Pulling the camera back beyond POV, there are novels and stories that exist because the author wanted to experiment with a narrative device. For instance, David Nicholls' One Day
of its narrative device (the story is told in vignettes a year apart on the same day). David Mitchell's Cloud Atlas
was built around its narrative device -- the narratives are nested like a Babuskha doll. Perhaps building a story around its narrative device is more common in literary fiction than it is in science-fiction, but it's certainly wrong to say that novelists "don't start with a device and then concoct an excuse for using it." I can't think of a work that was built around its POV in the same way, but that doesn't mean it's not out there. (And I have a hunch there's something very obvious that I'll smack myself in the head for not thinking of.)
On the other hand, I did not intend to write a short story in the form of a Socratic dialogue. It was the right decision, but I didn't plan to do that, and I have a not-terrible draft of the story that was written in the mode that I had envisioned the story (which was a Fritz Leiberesque fantasy, specifically something like "Lean Times in Lankhmar").
In short, writers have different reasons for deciding how they want to write. Some start with the story and decide on the device to get them there. Some start with the device and then decide on the story to use it. And some are given assignments in college creative writing classes where they have to use unexpected narrative elements -- like multiple first person narrators.