If you are sure that you have a really profitable trading system in front of you, you have developed it yourself, having previously tested it on a demo account, then you must strictly follow its rules
demo is good i agree but the main problem is the result we get from the demo actually this knowledge not works when trading in a real account.
What you can learn on demo account is how to click buy and sell buttons, apply charting functions and tools, open various charts and check price history. Demo account gives zero knowledge about how to build trading strategies but rather how to implement them in trading, trying first in risk-free environment.
The demo account makes it possible to really understand how to react, where to click and what to do, so I believe that it is necessary in practice.
the psychological aspect in any work gives a lot, and strongly influences the outcome of your work, therefore always take into account such aspects as psychology and many others
Yes, psychology has important aspects in trading, psychology in trading included how to control emotion when we get lost, eliminated anxiety during trades, maintain discipline, and more.
I think lots of psychological fortitude comes from experience too as well as reading books. No amount of reading can match the value of being in the trenches and feeling them feelings yourself