People with ADHD ("ADD" is a very outdated term) aren't always disorganized. In fact, they're often organized to an unusually high degree (sometimes to a fault). I've been diagnosed since 1996 and I rarely have more than 10 or 12 tabs open across all windows at a time. Paying close attention to organization and establishing routines to cut down on distractions and reduce the possibility of variation in daily activities are very common coping strategies.