Quote from Rabbitone:
My questions to you are: How do you know when the system is not working the way it is supposed to? How many consecutive losses are one too many? When should the system be reevaluated (shut off) and when should it be left running?
I don't mean to avoid your questions, but they all need to be answered in the context of the system one is trading, and the experience of the trader.
There is nothing more valuable than experience, because only with experience can a trader develop a sixth sense that tells him when there might be a problem.
If I've developed a system and know precisely why, how and when it functions, and I'm thrown for a couple losses, it isn't difficult to understand why, and what action to take. If I'm confused, then that's a sure sign I shouldn't be trading at the moment, or may not yet be prepared to trade at all.
And that only comes with experience. Because any system with positive expectancy can be further improved by engaging an experienced brain before pulling the trigger, or deciding that things just don't feel right.
This "feeling" thing can't be quantified, and can't be passed on to another trader. Which is why most mentors, including myself, ultimately find it frustrating to try to teach trading to someone else. But that's another story....