John Maynard Keynes, the famous economist who was the guiding light for economic policy for the world in the Great Depression of the 1930s, was once criticised for changing his view on a vital economic matter. His reply was one of the smartest and most rational of all time.
“When the facts change, I change my mind,” he said to his critic. “What do you do, sir?”
This is the issue we investors have to consider all the time. And it gives rise to this question: Have the facts changed so much that what looked like a good investment idea/strategy is now a bad one?