Many investors are satisfied if they do as well as the market or almost as well, but that should not be the case. Phil Ash, Co-Founder & CEO of Baton Investing, tells TheStreet's Jill Malandrino that once you get past 20 stocks in your portfolio, you are getting close to mirroring the market, which makes outperformance nearly impossible. There are six common investing methods that are likely to do more harm than good, but are easily avoidable. Ash touches on key areas such as diversification, tax-loss strategies, age limits and what you need to know to have enough money to retire on because just achieving market returns may not be enough.