After 27 years of trading and backtesting of seeking the highest winning percentage for day trading and short term methods, I radically changed what I had been doing. As the years have passed, I worked less on scores of entries and much more on defining when to pass on a signal and management of the trade once in. This past year has altered how I think in terms of what I want to accomplish in my day trading and testing. So now I spend my testing hours on designing methods that will offer the smallest losing percentages.
I use to only test what the "MAE," Max Avg. Excursion (how much a trade moves against a winning trade), so as I can find the "mean" to define the right Protective Stops. But I have taken it a step further, On my profitable days, I backtested what was my mean of intraday drawdown based on one contract.
So one way to save all your hard earned trading profits is finding out what your mean of drawdown is on your profitable days and when this figure is reached, cover all your positions and quit for the day.
I don't see this as a day where I traded poorly, unless of course I did not trade the rules I have made, I only see it as a day where my method did not work for that day. I am not a loser, the method lost. Tomorrow is another day.