The freedom for both GMs and players to declare what they want to do and do it, without any requirement to figure out what "move" your proposed action counts as. The freedom to not concern yourself with following narrative beats and pay-offs, but rather simply to live in an imagined world and make choices.
See, this is one of those things that's a bit hard to grasp--it's taking me a while as well. But this is why the games all say, "to do it, you have to do it." Moves aren't actions, skills, abilities, feats, or anything else like that. A move is simply a way to
move the story along.
And quite frankly, having to figure out what skill or feat or class ability you're going to use in a tradgame like D&D
is a requirement to figure out what your proposed action counts as. As someone else said, you're just so used to it, you've internalized it. I can't tell you how many times even the most experienced gamers at my table have had to look at their D&D sheets to remember if they had such-and-such an ability.
Example: say that the bad guys are closing in and one of the players says, "We gotta get out of here; where's the exit?"
In D&D, the DM might say "it's over there, but you think you hear growling from that direction," or they might say "roll Wisdom (Perception)," if the exit isn't immediately obvious.
In MotW, the Keeper might say "it's over there, but you think you hear growling from that direction" (which happens to be the Keeper's
Reveal Future Badness move), or they might say "it sounds like you're trying to
Read A Bad Situation. Roll +Sharp," if the exit isn't immediately obvious.
Same thing.
And if there's no move that stands out as the obvious choice, then there are basically two options: One, you can always have the player Act Under Pressure if there is, in fact, something putting pressure on them (for instance, having to get out of the area before whatever was growling comes after them); and two, you simply don't have them roll, especially if there's no pressure (such as if they go for the obvious exit and you know the monsters aren't actually there to attack them).
The PC does what they wanted to do, and you as the GM can put a cost there, if you like, in the form of the GM moves. For instance, if the PCs want to search the room, then in DW there's the Discern Realities move, which, if successfully rolled, allows you to find treasure. But if there's nothing standing in the way of them finding the treasure but time, you could also just say "You can search the room thoroughly, but it'll take some time to do so, and the noise you make while doing so is likely to draw attention. What do you do?" and this would likely be "Reveal Unwelcome Truth" or possibly "Show Signs Of An Approaching Threat." (I haven't read enough DW to know.)
That's it. You don't actually
pick your move. You don't examine your sheet looking for what best fits the action you want to do. You just talk it out. Really, the only reason GM moves even exist is to help out newbies.