Data. If you and someone else disagree look at the data, hell, even if you do agree, look at the data. Don't have any data? Get some data. You can't make decis

Data. If you and someone else disagree look at the data, hell, even if you do agree, look at the data. Don't have any data? Get some data. You can't make decisions, particularly big decisions without data. Gather all the data you can, analyze it, talk about it, and come to a consensus. If after doing all that you still can't come to a consensus, you need more data. If after that you are still deadlocked, flip a coin. (*By data I mean anything from market research, user feedback, the advisers experience, your experience etc. etc.)