As a role-player, what do you think is most often missing from the fantasy setting that Dungeon Masters provide?
Lack of detail is usually what's missing so players end up having to ask lots of questions to see what the Dungeon Master is seeing.
I agree with Gamemaster, that can be a hindrance when playing these types of games because you can miss things and miss out on loot sometimes. The Dungeon Master is only human after all. However, I also feel like too much detail can be a bad thing as well.
Details. Its all in the details. When you limit a scene or background to vague descriptions then two things happen; there is a disconnect between the character and the world they are in and you end up making choices based on assumptions you have to make because there isn't much to go on.
The fantasy might be missing. Fantasy is a theme but if everything is described in a non-fantastical way its hard to see your character in a fantasy. The adventure you are trying to present might sound more like an online puzzle rather than an interesting world of adventure.