As an adult with ADHD, I think it is possibly because you and your children have different ideas in the definition, perception and understanding of the problem itself and its consequences.
The children with ADHD do not think to ask for they may think doing something is not necessary to ask for permission just as it is not necessary to go to find their parents somewhere to ask for permission to have a pee when they play in the garden.
They may be careless about other people’s ideas or emotion but not viciously. They are just not good at decoding the face or reading microexpressions. Also they are not good at following verbal instructions. It is just the different way of their understanding.
My personal experience is not to use exaggerated abstract words but concrete words they can really understand.
For example, do not say if they did not do something, you would be crazy. But in fact you do not become crazy even though they did it. Therefore the relationship between the two things cannot be created.
Maybe you can say if they did not do something, you would feel unhappy, and then explain to them why and make them understand what you are feeling and how you are feeling.
In addition, maybe remind them of the unhappy experience in their practice, and make them understand the same feeling as yours.
Let them accept that acting with asking for permission sometimes will not make others unhappy. Maybe it is easier to make them follow your instructions. Because I believe that they are innocent and warmhearted children.
Be patient and calm. Do not only use verbal instructions. Show them what you do when you want to do something and do it before them. Because most children with ADHD are not good at verbal instructions, but they are visual learners. So if you want them to do what you want them to do, do it actually in front of them and do it for them with patience and love.
Additionally, try to be tolerant and caring, and patiently accept their behavior. Try not to use critical words to condemn them for it is not easy for them to accept these words which easily lead to resentment.
Don’t give up and in the end you will see the positive results.
(My Child Just Doesn’t Listen! And More Frustrating Discipline Problems)
(Auditory Processing Disorder: Where to Go for Help)