How often have you been to a lessons learnt meeting and bitten your tongue? The lessons are very rarely new because the mistakes are not new!
However when the lessons have been learnt and are applied as part of a process delivery is slowed down, costs go up and then the business is frustrated by the perception that the benefits it wants realised are diluted!
Change the methodology; bring in new terms such as Minimum Viable Product, bypass the process and get everyone onboard and off we go onto make the same mistakes and learn once again how quickly experience is lost!
At the end of the day it is these repeated mistakes by many very clever people that keep a great many of us employed . . .