Is discipline in Forex so important indeed?

Yes, I'm absolutely convinced, it has a paramount importance in everyones trading.
Let me get an example for you.

Suppose, a trader found an allegedly winning system. He brought it to MT4 and back-tested it. the system promised high yields. Our hero is ready to trade it.

But, although the factor of system potentials was positive, there is still one problem left. It is a human factor.
Trading is done by humans, unless a trader uses an automated system... this article is not for such traders, they should be fine. Do read on if you trade manually.

Let's go back to our example. Back-testing results were promising, but how smooth was the system performing? Did it require some nerves from times to times to hold a position open? If so, how prepared is a trader to trust a system and follow the rules without involving any emotions.

Discipline is a difficult part of the trading. It is most important part and it is most crucial part in trading success.
Many novice traders pay very little attention to discipline recommendations given all the time by experienced traders. But inevitably every trader comes to understanding the word "DISCIPLINE" in Forex.