According to Wikipedia, rosy retrospection means: “People judge the past disproportionately more positively than they judge the present.”
The future is unknown and the present is urgent. Luckily the past is our playground. We’ve been there, it’s gone and now we can deal with it the way we want to.
It’s hard to admit but most projects will never be properly evaluated. It’s easier to deal with them as a succes so we can focus on the next priority. Companies can be pretty whimsical when it comes to their own priorities. But user priorities are a lot more stable. Focusing on the user therefore will give your company a clear focus.
That’s why UX really should be in the heart of your organisation. Try it, you’ll see that you will bury your old priorities in no time with a kind but firm goodbye.