Why software projects take longer than you think: a statistical model (2019)
All this smokes and mirrors, when the reality is: if you gave accurate estimates, you'd get reprimanded, not get the project approved, etc. Same reason that infrastructure project go over budget. The way anything actually gets done is by initially being overly optimistic, ignoring potential future problems, getting the project approved, then lock it in via sunk costs, now as problems turn up, you can claim it could never had been foreseen, it's an impossibly hard problem bla bla. But best to bail from the vicinity of the project once reality starts to manifest itself. By that time you should be on the next project perhaps at the next company again promising the stars.