Macro Assumptions
The worst assumptions to make on any project are when you start contemplating macro-level variables.
You cannot control macro-level variables in any meaningful way, and often they fall in to the extreme quadrants of predictability and changeability.
Two of the biggest red flags to watch out for is when someone is trying to predict a macro-level variable – the future value of the stock market or a change to the law.
Or when someone is trying to change a macro-level variable – the direction the Earth spins or the time that the sun rises in the East.