The first globe I owned was a cheap light up one from a drugstore, the kind with a bulb inside that made the oceans glow a weird blue. It taught me that a globe is a piece of furniture before it's a reference tool, and if it looks wrong in the room nobody is spinning it to find Portugal.
When you're looking at one in a shop or checking it over the day it arrives, run your hand along the seam where the two hemispheres meet, because on the flimsier ones that join is rough or slightly uneven and it only gets worse with handling. Check the base and the arm that holds the sphere, not just whether they look sturdy in a photo, but whether the globe actually sits straight and doesn't list to one side like it's had a long night. Give it a spin. A good one turns smoothly and quietly on its axis, a bad one catches or wobbles, and you'll notice that every single time you walk past it. If it's the kind with a stand rather than a full frame, check the weight of the base against the size of the sphere, because a heavy globe on a light base is how you end up with it on the floor.
If you don't own one yet, start plain. A simple sphere on a wood or metal stand, in a finish that matches something else you already own rather than fighting it, does more for a room than one covered in gold oceans or a map styled to look three hundred years old. Those antiqued versions can be lovely, but they read as a lot in a room that doesn't have much else going on, and they date a shelf faster than a plain one does. The plain version earns its spot in a study, a kid's bedroom, a living room shelf, almost anywhere, which is exactly what you want from your first one.
Size is where people get this wrong more than anything else. A globe that looks reasonable on a desk in a shop can look enormous on a narrow console table at home, or lost entirely on a wide bookcase, so measure the surface it's going on and picture the globe taking up a third of that space, not the whole thing. On a desk, leave room for the lamp and the stack of books you're actually going to use, a globe that forces everything else to the edges stops being a nice object and starts being an obstacle. On a shelf, a smaller globe tucked among books reads as considered, a huge one sitting alone on an empty shelf reads as though you ran out of ideas for what to put there.
This suits a home where a few good objects get noticed because there isn't clutter competing with them.