Quote from Cutten:
I don't think there's any such thing as innate willpower. If you look at people who have amazing "willpower"/discipline in one area, often they are incredibly undisciplined in other areas. Many billionaires are fat and can't diet. Some great athletes have a drink problem and can't stop. World class entertainers hooked on drugs. Artists who can't quit smoking.
Have you ever seen a child who was naturally disciplined without any upbringing to create that behaviour?
Clearly there is no such thing as inherent discipline.
IMO discipline is the habit of doing productive work, and avoiding the temptation to indulge in short-term gratification instead.
Anyone who has started exercising, dieting, giving up smoking or drinking etc will tell you that it's hardest at the start, and becomes easier as you do it for longer & longer. The reason is that habitual behaviour is easy to do, it requires little energy, you can do it without thinking. Non-habitual behaviour is difficult - you forget about it a lot, you procrastinate, when you realise you should do it then often you don't feel like it, and when you do get down to it, it's easy to become distracted or bored and stop early.
I think the way to achieve discipline is to clearly define the steps, time, and effort needed to make the behaviour a habit. Your goal should not be to lose 20kg, but rather to make eating more healthily a habit. The latter is a much easier goal than the former.
The same way, instead of saying "I am going to become a millionaire through trading", you should say "I'm going to make it a habit to follow the steps necessary to trade well" (assuming you know what they are - limit risk, maximise market experience/research to find legitimate edges, then test & implement them as rigorously as possible). I've never found that affirmations made much of a difference to my P&L. But the times when I was getting into work at 630am every day, or taking time out to do research on methods after the market close, definitely paid dividends.