I've been DMing now for about 22 years and it took me most of that time to learn one important lesson: Never prepare anything for the game that you don't enjoy preparing. The add-on to that is that you should never prepare anything where the preparation isn't the reward unto itself.
I know it's a little broad. You have to have at least a basic adventure or something similar for the session, whether it's pregen or winging it. However, anything extra you put together, from handouts to maps to descriptions to backstory to campaign notes to special treasure cards to whatever else you can think of is all stuff the DM should be doing because the DM enjoys doing it. (Or maybe because they feel/believe they cannot run the session with out.) That's all that matters.
Yes, sometimes players will love something you do. Sometimes they will ooh and ah over it. Most of the time, the majority of the players will never notice the work you put into it. That's just how players are. Unless they DM a lot, they just don't get it.
I realize my comments sound very cynical. Well, they probably are. That doesn't mean they aren't spot on.
It's a common curse of being a DM. There was even a strip about it recently in
DM of the Rings.
Don't let this get you down. It shouldn't take the fun out of the game, it should just let you know where to focus your efforts so you get the most fun out of the game.
As a side-note on this: I don't believe this is a RPG player thing. This is a human thing. I see the same thing at work. People don't care about the great training materials you create to make their job easier. People don't think about all the work you did to get project X done on time. Most people just generally don't notice the things that happen outside of their own headspace; they just don't realize.
Yeah, okay, definitely cynical.