I think on average, when someone tells you how "good" a piece is, they're not sitting around evaluating your anatomy, composition, or lighting choices. Chances are they're talking about how much they LIKE the piece, which can cover a whooooole lot of things. It could have emotional resonance relating to something they're going through right now. It could be their favorite color. It could be something as unrelated as they really like ladybugs, and this pic sure does have a lot of ladybugs. It doesn't mean your other works are bad - it just means they don't have as many ladybugs.
Although if this is a person who DOES sit around evaluating anatomy, composition, and lighting choices, now's a great chance to ask why they think this one works better than the rest.