Every trader needs a trading plan, and then they need to adhere to that plan. If you are not adhering to a trading plan, or you don’t even have one created, then you don’t have a trading business.
You are like a gym that isn’t maintaining a profit/loss or balance sheet. They might be able to convince people who look on from a distance that they have a business, but it is only a matter of time before the tax office is going to come along and burst their bubble, charge them fees to do it, and require them to create their financials. At that point - if they don’t have the 15-20k required to reconstruct their financials, they will have to close the doors.
Your trading plan is what you should think of as your ‘minimum viable product’. Many aspiring traders keep their trading system rules in their head, not appreciating the importance of comprehensively writing them down. If you don’t write them all down, then you can’t establish consistency - and you can’t get very far as a trader without first establishing consistency.
Trading rules can be a component of a trading plan, but for me are a more personal thing. Not every professional trader will talk about them as separate from a trading plan, and I expect not every trader adheres to the view that separate rules to the specifics of a plan are necessary.
I think that in the same way we give children rules, we similarly should give ourselves rules - beyond our trading system rules - in order to more safely travel the forex terrain. There is a lot to learn on our trading journey, and building up a list of rules is a great way to distil the trading wisdom that we learn along the way, and have it available to us in a form that is succinct and efficient.