I usually hate doing the "please read this article," but I think this piece describes really well the challenges faced by people with ADHD because if their lack of executive function. Important quote:

Tasks in the neurotypical world have a beginning, a middle, and an end. Individuals with ADHD don’t know where and how to start, since they can’t find the beginning. They jump into the middle of a task and work in all directions at once.

And I would add to that - if they jump in at all. A person with depression may not be folding their laundry because they cannot get out of bed. A person with ADHD may be up and around and doing a bunch of things but not the things they need to be doing, like folding laundry, because they don't know where to start, and it's way too overwhelming.

Then, it's also possible to have depression and ADHD, especially since being neurodivergent can be fucking depressing. Then it's a double whammy.

I hope this helps explain it.