podcast question: when you download podcasts are their filenames all nice w/ consistent episode numbers & stuff, or are they all over the place?

I'm using an RSS reader & downloading mp3s via hyperlink; about half of them have filenames like "default_tc.mp3" or "459c1022-aa0b-d288-0dc9-7f36f5300997.mp3"

& I'm starting to wonder if maybe that's not the normal podcast experience