Always keep in mind that some unexpected event like a natural disaster, war or unexpected death of a political leader could throw the whole market into confusion. You can succeed without being the perfect technical analyst but you can’t make money with world foreign exchange trading without understanding risk management. If you’re risking too much on each trade then at some point or another your funds will be wiped out. All systems have their swings and roundabouts and if your risk is too high, your account balance may not be able to recover from the downs. And if your stop loss is too close to your entry point, it’s going to be triggered too soon.
So risk must be optimised for your system. Only take the higher figure if losing your complete balance would not be a disaster. Generally, the additional cash a trader has in their account, the more careful they’re with it.
Some traders consider that having a set risk per trade is too rigid and the chance should depend on the power of a signal. That’s fine so long as the variable risk is still defined according to the system. What you need to avoid is varying the chance dependent on intuition, or dependent on the result that you had from the last trade.