We’re all chronic under-estimators by default so I wouldn’t beat yourself up over that one! The old planning fallacy is very well studied and documented. Humans

We’re all chronic under-estimators by default so I wouldn’t beat yourself up over that one! The old planning fallacy is very well studied and documented. Humans are terrible at estimating by default unfortunately :-( but it’s not that hard to be conscientious about getting more accurate. For me, the secret is to just delegate to a tool that gives me estimates based on my past performance. The cost to me is nothing more than logging an estimate up front and recording what it ended up after the fact. Doing that for a few weeks rapidly steers you to breaking your work into small chunks because it’s too hard to make the recording work otherwise. Turns out small chunks of standalone useful outcomes are optimal anyway for 1001 other reasons. As for saying no - one way could be to find a role model somewhere close around you, it should be easier to copy what they do if they’re in the same org structure and facing the same struggles. You can’t just assume to flick a switch and behave like them, everyone around you has an expectation of how you behave right now, so you have to be fairly active about signalling to people they should update their perceptions.