It looks like Dennis Gartman got caught out by recent market volatility:
That being said he appears to be sticking to his “Not-So-Simple (but materially fewer) Rules of Trading“.
Be it investor or trader, it is impossible to get it right all the time. Even the Oracle of Omaha legend that is Warren Buffet, is prone to the odd mistake.
It really comes down to having a good balance between Risk/Reward and Win/Loss ratio as discussed in the following link: Risk Reward Win Loss Ratio