If they don't have anything to design they are fired and have to go find another job. So they actively look for things to design and propose changes.

Remember the moz://a brand change? I wonder if there is any way to measure the benefits of it, except for the paychecks to the designers.

Edit: I realized that it could be another thing. They are signalling they are alive and well. Similar to buying a 200k sport car. See how much money I can afford to do without?