The late Charlie Munger (Warren Buffett’s partner at Berkshire Hathaway once remarked “It is remarkable how much long-term advantage people like us have gotten by trying to be consistently not stupid, instead of trying to be very intelligent..”
One way to be ”to be consistently not stupid” is to learn from the mistakes of others. A good place to start is a recent Entrepreneur Magazine article which offers an important checklist: “Here Are the Top 50 Mistakes I’ve Seen Kill New Companies”. Many of these might apply to a new division or product line as well!