This is just my hypothesis; however, it is based on 20 years as an OCD therapist and on being married to an intensely (and lovely) ADHD woman.
I have seen a strong correlation between people with ADHD/ADD (and bipolar) and Pure OCD - especially if a creative, extroverted person had those natural attributes suppressed or repressed during childhood by parents, school, bullying, or some other traumatic event.
In this video, I try to outline the patterns I have witnessed. It is not scientific, but it is what I have seen time and time again, and so many people have told me that this knowledge has changed their lives.
Much love, John