Lacking self-control robs you of free will. This is one of the most tragic consequences of ADHD. You might think you’re doing what you desire. Yet if you can’t inhibit your behaviour, you miss out on the delay between an event and your response…that delay empowers you to choose freely…That’s what I mean by self-control: the ability to choose something other than your initial impulse so you can get something in the future that you want more or that is better for your long-term welfare and happiness.

…“Free will” is just another way of saying we have the capacity to deliberate on our options to act, which in turn gives us the opportunity to choose what’s best for us down the road.

From Taking Charge of Adult ADHD by Russell A. Barkley