Experience is the best teacher. Though that certainly is true life is too short for one to learn everything via experience(s). Since mistakes can be quite costly [literally] both in real life and the business world it would be profitable to learn all you can from the mistakes others have made, know the pitfalls and avoid them and you'll be spared a lot of pain and losses. If you've seen a business collapse, find out why it happened. Seen a man go bankrupt? Learn from his mistakes lest you find you also find yourself in the same straits.