So I have some epub files, I open in Calibre, and if they already have a cover, I just convert to mobi without editing any metadata or covers. Assuming they already had covers.
So given the advice above, even if the epub books showed a cover, I clicked to download metadata anyway, convert to mobi, and sure enough, the cover of the book show in both my Docs tab and on the Bookshelf front page. (What a PITA, having to do this for every epub file?)
However, a couple of books I tried, had the correct title and author in the fields, but when I clicked to download metadata, it said nothing could be found, try less specific details. So I tried with just the authors' name, and it still didn't find any info for the book.
Anyone else experience this kind of thing?