It's a fantasy role-playing game.

DM: You are Fjord, a half-orc warlock . You are the member of the famous group of adventurers. Previously,  Having learned all that they can about you's odd incident, the party embarks on their second day of travel.
DM: You, on the wall, dance off the way, leap as it goes up. All right, and I believe that's all the gnolls immediately in the vicinity that are in combat. That ends the gnolls' turn. Fjord, you're up.
Player: Yeah, great, awesome, sweet. Can I use Eldritch Blast against the big fucking guy, because he didn't get any closer for a melee attack, right?
DM: You're still within his attack range, because he has the glaive. You do have disadvantage on Eldritch Blast.
Player: Oh. Imma fucking move out of his attack range. Does that give him attack of opportunity? Yeah, I'm doing that anyway. I'm going to move back towards the corner where I was going.
DM: Right there?
Player: No, all the way back. Back towards my original hiding place.
DM: You pull back to the corner there. As you pull back, he takes a step forward and reaches out with the glaive to try and strike you.
