This looks not a serious advice by person with 20 years experience on stocks trading since traders on stock frequently do day trading for a living. Besides a real pro traders sets there profit and stop loss in every trade that they made daily so it's impossible for them to everything for just doing it. An experienced trader will always be disciplined and follow his trading rule book on all his trades.

I’m not suggesting day trading is good but it's not bad either if you knew how to properly execute it.