Successful traders don’t need to trade to be successful; their trading success is an extension of– and is permitted by– their other life accomplishments. The markets can be challenging, rewarding arenas; but they are not life and they cannot fulfill the panoply of legitimate human needs. To pursue one’s development as a trader at the expense of one’s personal development is to court the very emotional interference that generates inconsistent, substandard results.
– Brett Steenbarger, The Psychology of Trading