I would not consider myself a person who has great self-discipline.
The last time I can really remember having self-discipline was when I was in 6th grade and vowed to write in my journal every day for a year – and did it. That was kind of awhile ago.
More than anything, I’m pretty rules-driven or expectations-driven, so if someone tells me I’ll get in trouble if I do XYZ, I am going to stay the heck away from anything that looks like XYZ. On the other hand, behaviors like eating healthy or working out that aren’t driven by punishment but are driven by, you know, things like an increased risk of heart disease? Nah, I’m not all that motivated. Hence why I’ve worked the last 8 months or so on losing weight.