1. The document discusses why investing is relevant to managerial decision making and describes some of the cognitive biases and errors that can lead to poor investment decisions. 2. It outlines several main causes of poor investment decisions, including overconfidence, optimism bias, denial of randomness, and issues with framing gains and losses. 3. Finally, it provides some steps that can be taken to make better investment decisions, such as recognizing the impossibility of outsmarting the market, determining goals and sticking to plans objectively, and overcoming cognitive biases through awareness and planning.