TL;DR: ADHD isn't what people think it is. It's worth learning about, even if you don't have it. This YouTube channel is very clear and informative:
https://youtube.com/c/HowtoADHDADHD is a disastrously wrong name for the disorder. There is no deficit in attention, and hyperactivity is only as common as inattentiveness, and neither of the two is a primary symptom.
Executive dysfunction is the primary aspect of ADHD. Poor working (short term) memory is the second.
We get distracted because we can't choose where to put our focus. We miss important details in conversations because we tried to listen while also thinking about something else, and lost both details to a mental stack overflow. We get hyperactive because we are understimulated and can't be intentionally calm. We don't do homework or wash dishes or finish projects because we can't intentionally get started on anything.