You should be a fan of Dick Morris and his methodology.
As Duncan Watts noted about his disagreement with Malcolm Gladwell on the significance of inluencers: " "My models might be totally wrong," he says cheerfully. "But at least I'm clear about what I'm saying. You can look at them, and tell me if you disagree.
But none of these other thinkers are actually clear about what they're saying. You can't tell if they're wrong."
Dick Morris reads the polls and notices that they have sampled more Democratics, who have traditionally voted less often than their Republican neighbors. Romney Wins!
Dick Morris knows where he went wrong.
He based his turn-out model on an assumption that 2008 would regress to 2004.
His 
prediction was wrong, but he understands his mistake.
Decision theorists call this a "base-rate" error. What errors are you making in calculating your base-rate of customers?
Will you be honest like Dick Morris and admit your mistake?
Or will you have some comforting story to tell about your lack of sales?
