It's one of those things that seems like a good idea at the time. The hot thing used to be small .32 autos. First the Seecamp, then the Beretta Tomcat, the Autauga (now almost forgotten), KelTec P32, NAA offerings, and probably some that I forgot. Then engineers came up designs to make their product stand apart by making a similar size gun in .380. Thus the next generation of small autos.

In the "it's seem like a good idea" category, it goes alongside the very light alloy frame .357 magnum revolvers in terms of utility. Some people learn to use their mouse guns well, others find them a bit snappy, that reliability might be an issue (Keltecs seem to be iffy), and that the short sight radius and limited sights make hitting anything a challenge.