Introspection: What I THINK I can do doesn't take attention disorder into account.
Examples:
Kid's electronic toy that we loved is broken. Instead of throwing it away, I put it in a box because "surely, I'll find the time to fix it"
After moving, valuables are "temporarily" in plastic bags, because I'll buy & assemble a showcase soon enough.
None of these things ever happen. I make the planning as if I did not an attention disorder. Although I had it all my life.
Now that I'm in treatment, I would have thought that my brain works in a way I'd need to get used to. But no, it just works in the way I always assumed when I made a plan.
It's just so strange that the planning seems to assume an intact prefrontal cortex, rather than adjusting to how it actually works.
In my experience, ADHD meds make it easier to stay in task rather than getting distracted, but they don't make it any easier for me to actually start tasks!