The really hard part sometimes is getting political support within an organization. Someone usually went to a lot of trouble to argue that a feature was worth building, and a lot of senior people had to agree to it. A bunch of folks worked on it. Now you're asking them to admit that it didn't get traction, and more work should be done to remove it (and maybe annoy some customers along the way.)

It's necessary, and it should be done, but it's often unpalatable and doesn't happen, leading to bloatware.