The third major problem: Project Manager/Scheduler/Sales/Customer doing one/any/all of: not believing the input of the SME (you) when they ask for input develo

The third major problem: Project Manager/Scheduler/Sales/Customer doing one/any/all of: not believing the input of the SME (you) when they ask for input developing the schedule, overpromising, expecting the world, or so many other problems. Too many times in my own field (heavy construction) the scheduler has asked me how long it will take to do a given task, and it is actually reasonably quantifiable to say "It will take my crew X days to move Y volume of material at Z/shift" only to be told "Well our proposal only allocated X-5 days and budgeted a Crew of <your chosen size - 4> for that task. Figure it out."