reactions to names sibling gift exchange

i don’t understand why they react in the way they do to the names they get like saying “oh this is a good one” as if the others aren’t? or acting disappointed when they get someone they didn’t want. their your siblings you should at least have an idea of what to get them and if not i’m sure one of your many other siblings can help. imagine how that person must feel? knowing they or not a “good choice”