Your first plan cannot be "perfect" but that should not be an excuse for not making it "complete"---as complete as you can. If you know you'll have to hire at

Your first plan cannot be "perfect" but that should not be an excuse for not making it "complete"---as complete as you can. If you know you'll have to hire at least 2 engineers, for example, the plan should contain an entry for that. Think about Donald Rumsfeld's advice: your first plan should contain all of the known knowns, good estimates for known unknowns, and wiggle room for the unknown unknowns. And keep it as complete as possible. If your board, or your investors ask you where things stand, you must be able to give them as complete of an answer as is humanly possible.