I worked at a company that had invested big $$$ into an agile tool without consulting the teams if it was adequate for their needs. For a month or 2, the teams used the tool as required. Eventually, when the boss turned his back, each team quietly found a tool. Because they were being quiet, each team found a different tool from every other team. They were actually tracking their progress in both systems, but the expensive one was only being updated afterwards. Everyone would sit around the easy-to-use tool and plan things, and then 1 unlucky soul had to transcribe it into the crappy tool. This actually sped things up because the crappy tool would waste time x5, where the combination of tools only wasted time x1. (And we usually got a non-developer to do the transcribing, too.)
Eventually, the whole thing came to light and the company was forced to admit how stupid they were being.
See, they had paid for a year's service of the bad tool, and they were adamant that they get their money's worth. They were absolutely blind to how much money they were wasting daily. The sunk cost was sunk. There was no way to recover from that, and the tool just couldn't be salvaged.
