ADHD and the military: Why do some militaries exclude people who thrive under pressure?

I don’t have definitive list of countries, but I’ve talked to people online from various nations, some were excluded from joining the military because of their diagnosis. Now I’m sure there is data backing up why they don’t want people with an ADHD diagnosis in the army. Perhaps stats and trends seen by analysts that

Rant and analysis: Willpower and the relationship to mental health and combat.

We often associate will power with an impeccable discipline. The ability to focus without distraction even through discomfort on what they do and what they want. By this definition, many people who need to Stim or get over stimulated often have low will power, because their threshold of self control and toleration is a great