Feel free to answer using any sport although my example comes from baseball.
A recent example was the Pittsburgh Pirates and Los Angeles Angels trading (failed) closers, Jason Grilli and Ernesto Frieri.
Is it true that many such trades are predicated on the theory that a "change of scenery" would help one or both players?
Apart from that, the Angels got a more experienced pitcher who rebounded faster for the playoff run, while the Pirates indulged in their preference for "youth" with the much-younger Frieri. Could "team fit" be another important factor in such trades?