Quote from Chandler in The One with Chandler in a Box
Ross: Maybe Phoebe will switch with me. Chandler: No, no, no. You don't want to do that. Then you're going to get stuck with Rachel, and she exchanges every gift she ever gets. Ross: No, that's not true. I got her lots of stuff she never took back. Chandler: Like? Ross: Like that gold necklace I got her last year. Chandler: And when was the last time you saw her wear it? Ross: Well, she wore it all Christmas day and then ... Chandler: Big dog?