Hyperfocus
For all that scattered attention, mindwandering, forgetfulness and disorganization there is an even more confusing aspect to ADHD that is often cited as evidence for why the person can’t have it at all. Hyperfocus, the ability to lose time and be completely absorbed by some interesting occupation, and interesting is the crucial word here, seems to suggest that the adhder can pay attention when it suits them.
Better Late than Never 