I hate that when my bettas dont acknowledge my cute decorations!
Actually it depends on the personality of the fish I think. I have some that will immediately inspect or check out the new addition, some will ignore it completely.
I put a long hollow log into my giant guy's tank because he apparently loves to hide and nap and hide near the bottom of his tank. he immedately went through it. now if I can't find him I know to look in the log and there he is, chillin. LOL