Pure Nightmare

[Cassiopeia]

Some players? I would say, most of the players!
Especially when you play a game more than once. You might play it the first time, thinking, alright, I haven't found everything, that's okay. (Although for me it's never okay, lol.) But the next time you play it, you sure want to do better and find more. Hence you have to explore thoroughly.

[Indinera]

As a player, I'm usually satisfied with "my best". I also enjoy owning the monsters in the most difficult mode. I can live with missing some quests/secret rooms.
That probably influences the way I make my games, ie very hard to find secrets, and monsters with strategies to defeat them, no matter how strong they are.

[Cassiopeia]

I'm totally the other way around. I'm usually perfectly happy with Normal Mode, but I do have to find everything and solve all quests. Although I'm sure there's not one game of yours where "everything" has been found by anyone. There will always be some remaining secrets.
In DSC I just found out on my last playthrough that stepping on that one red skull in the middle of nowhere brings me a lot of goodies.
I have to admit though, that beating DSC in PN was really satisfying. However, I knew what I was doing it for. I don't think I'd go through this just for the sake of defeating the game.

Btw - "when hell freezes" will have a different meaning as of now.