People around me often praise me as a disciplined person. It's one of the few compliments that I really enjoy when I get it, because I pride myself on working hard on my discipline. But in truth, I don't actually think I have discipline that is substantially better than my peer group. Among the general population, sure, perhaps I am 80th percentile or better. But I know many successful and diligent people, and most of them are much more disciplined than I am.
There are some ways in which my discipline is very poor. I've been without a traditional job for the last two years, and without deadlines to meet, my procrastination is often ridiculous. This entire blog post is being written at a time when I have many other errands that I have been meaning to do for at least a couple of weeks.
But there are many aspects in which I am very disciplined. Nutrition is probably the one area where I am very good relative to the field. I eat very clean, even by the standards of a serious athlete, and often to the chagrin of my girlfriend (who has at times accused me of orthorexia). But even this "discipline" is just a hack. I am not disciplined in the sense that I am much better than average at avoiding an open bag of potato chips or a carton of ice cream in my living room. But I am very good at walking past the potato chips and ice cream in the grocery store. I am very good at keeping my fridge full packed with vegetables and meats.
One skill which I have developed is a very high ability to delay gratification. I have managed to frame things in a situation where I am often able to convince myself that the thing that I want right now will be much better if I simply wait until the future. It doesn't really matter what the thing is; I have learned to become very good at delaying its consumption. Particularly in the areas of diet and saving money, this skill has been very useful.