Hands break most often because the hand is a moving assembly of many small parts, and in photographs it is almost always partly occluded. Models get few unambiguous examples, which is where extra fingers and strange bends come from.
In practice something simple helps: pick a frame where the hands do not cover the torso and do not overlap each other. Arms hanging at the sides come out noticeably more reliably than arms crossed on the chest or raised to the face.
With try-ons, watch the sleeve edge — that is where the artefact usually shows up. If the item has a long sleeve and the arms are bent in the source, the odds of a miss go up.
And the rule that works best: do not argue with one bad result, rerun it. The first two attempts are free, and the spread between runs is wider on hands than on any other part of the frame.
