Why do many EAs fail while the same strategy works perfectly in manual trading? - page 3

[Garry Paul Smith]

Many EAs fail not because the strategy is bad, but because the EA was optimized for an artificial environment. have seen so many EAs hat have a beautiful equity curve in a backtest result but in a real enviroment its the complete opposite

[Arno Olivier]

And that is the exact two contradictories about manual and automated trading. Manual traders should leave their emotions and thinking behind when they enter a trade, and stick to the rules(disciplined). Automated trading is rules bound set and cant think outside the script but is disciplined?