Mine are all DIY, which suited my very limited budget and tackles
@tinkerdan's point about owning the rights, but proved to be a very painful learning curve. Each cover that I've done has gone through multiple iterations of design, and then multiple iterations to refine the chosen design down to something I'm happy with.
I did look at premade, because you can pick those up incredibly cheaply, and within my budget, but as with all these things, you get what you pay for. My feeling, when I looked at the low-end premades, was that they looked as cheap as the price tag, and put the biggest possible capital G in generic. I imagine that if you're writing something in a big, popular genre such as romance or werewolves, those generic covers are fine, but I didn't think I was going to find anything that even vaguely fitted my peculiar books. By the time I was looking at a service that would customise enough to work for me, the price tag was rising sharply, but at that point you are paying someone for hours of their time.
(To put budgets in
my context, a low-end premade costs about the same as a new 6-foot field gate or half a dozen new fence posts, and buying those has to take priority.
)
One of the issues I did run into was the difference between ebook and pod covers. Ebook is relatively easy since it is just the image in roughly the right proportions to look OK on Amazon, but the pod cover needs all of that PLUS the spine and back. Clearly the spine and back can be plain, with nothing but title, blurb and all the housekeeping stuff like ISBNs, but you still need some meaningful control over the cover image to incorporate it into the pod layout, or pay your designer to do that second layout. (I started looking at the pod cover for my space opera with a view to getting physical copies into local libraries, but that was about a year ago, just before the lockdowns started, and I've not taken it any further since.)
