Mistake
I started using the various POD services without having any familiarity. I had to learn many things and many I still have to learn. I made mistakes and I will surely make more. One mistake I made and which I strongly advise you to avoid is relying on a single POD service. When one of these services started selling products with my graphics, I felt gratified. So I just focused on that service. A well-known POD Marketplace where my efforts were progressively rewarded. Over time (years) I managed to get license to sell FanArt (of popular brands) and also to make my store often trend within the Marketplace.
Why not rely on a single POD service offered by a Marketplace?
Here because
After years of work, with no warning, the account gets suspended and all you get is an autoresponder that basically says:
Hey, your job is lost but there's nothing we can do to figure out why... that's how ours works service!
That's how it works and you can't do anything about it
Do they provide a service that protects the artist?
Do they prevent the artist's drawings from being stolen?
Do they prevent the drawings stolen from the artist from being sold on the same marketplace?
Do they avoid spam tagging?
The AI or robots... what are they programmed for? To protect who or what?
I will avoid answering these questions but I would like those who start using PODs to ask themselves.