Beige is the color that makes a room look finished without anyone being able to say why, and that is the whole case for a beige rug. It sits under furniture instead of competing with it, it hides the normal dust and crumbs of a house that gets lived in, and it still looks like you made a decision rather than just not picked a color at all.
How it wears depends a lot on what it is actually made from, and that is worth checking before you buy rather than after. Wool holds up the longest and bounces back after a chair leg sits on it for a year, but it costs more and sheds for the first few weeks, which is normal and not a fault. The cheaper synthetic ones flatten in the high traffic spots within a couple of seasons, usually right in front of a sofa or a kitchen sink, and once that pile is crushed it does not come back no matter how much you vacuum it. On delivery day, unroll it and check the edges are properly bound and not just glued, run your hand across the pile to feel for any thin patches, and look at the backing if there is one, because a rug that is going to curl at the corners within a month usually tells you so straight away if you look closely. Beige also shows stains differently than darker colors, not more of them, just more visibly, so a rug with some fleck or a subtle pattern in the weave will hide a coffee spill far better than a flat, solid beige will. Clean spills quickly with a cloth and plain water first, and get it properly shampooed once a year if it is wool, because grit ground into the base of the fibers is what actually wears a rug out, not the walking on it. It sits well against darker wood floors and against furniture in almost any wood tone, and it is forgiving next to a lot of mismatched hand me down furniture, which is most people's living rooms at some point, mine included. It also works as a quiet background to a patterned cushion or a colorful throw without the rug itself shouting for attention. Living rooms and bedrooms suit it best, especially ones that get a lot of natural light, since beige can look a little flat and gray in a dim north facing room. It is a good fit for a rented apartment where you cannot change the floor but want the room to feel warmer, and for family houses where you want something that reads as calm even when the rest of the room is not.