The moment this kind of piece earned its keep for me wasn't anywhere grand, it was a narrow hallway in a house with one tiny closet and three people's coats, shoes, and a box of Christmas lights nobody could ever find in December. A plain cabinet with doors, nothing fancy, went in against the one bare stretch of wall, and suddenly the hallway had a function instead of just being the place you dumped things on your way past. That's the real test for a storage unit. Not whether it looks good in a room that's already sorted, but whether it quietly fixes a room that isn't.
Where it goes wrong is when people ask it to be furniture and storage at the same time and expect it to win both arguments. A deep cabinet in a small dining room will eat four inches of walking space you didn't know you needed, and a tall one in a low ceilinged room makes the ceiling the problem, not the cabinet. If you're short on floor space, look at something that goes up a wall instead of out into the room, because the inches you save matter more than people admit until they're trying to pull a chair out at dinner.
In an ordinary room, this sits well with things you probably already own rather than anything you'd go buy specially. A plain cabinet next to a bookshelf with mismatched paperbacks looks intentional. One in a laundry room next to an ironing board and a basket of single socks looks like sense, not style. It doesn't need a matching chest of drawers across the room or a coordinated handle set, in fact a little mismatch between pieces in the same room usually reads as a house lived in rather than staged, which is the whole point of a home that isn't a showroom.
What it fights is glossy, high shine furniture nearby, a lacquered table or a mirrored dresser will make a plain storage cabinet look like the help, standing there holding coats while something flashier gets the attention. It also struggles in a room that's already busy with pattern, a heavily patterned rug and wallpaper and then a boldly finished cabinet on top is one thing too many for the eye, and the room stops being a room and starts being an argument.
The mistake to avoid is buying one before you've measured the doorway it has to get through, not just the wall space it'll sit against. I've seen a cabinet stuck sideways in a stairwell for an afternoon because nobody checked.