If you want to be a bad product manager, answer a question even when you’re not sure of an answer. If you want to be a good product manager, do not be afraid to say “I don’t know.”

If you want to be a bad product manager, have a low-cost strategy. If you want to be a good product manager, do not pursue a low cost strategy unless you truly are offering a commodity product that can not be differentiated at all from the competition.

If you want to be a bad product manager, worry about your current competitors. If you want to be a good product manager, worry more about your potential future competitors than your current competitors.

If you want to be a bad product manager, don’t evaluate your performance or attempt to improve. If you want to be a good product manager, measure your effectiveness and work to improve.