ADHDers can do anything once, or even occasionally.  The challenge is to do things consistently - like getting to work on time twenty-nine out of thirty days.  The goal of treatment is to help people with ADHD be more consistent.  You may want to be less forgetful or less distracted.  Perhaps you want to procrastinate less.  Notice the word is "less," not "never".  No one can be perfect.  So even with your best effort and the best treatment, you will still blow it sometimes.
 
You'll be happier starting with reasonable expectations and flexible objectives.  If you, or your family members and treatment providers, have unreasonable expectations or set objectives carved in stone, you'll be disappointed.  How can you ever be satisfied with the results of your treatment if you're attitude is, "If I achieve my expectations, I will be happy; if I fall short, I have no choice but to be unhappy"?
 
A better approach, one that has been my guiding philosophy as a therapist, is:

I work hard to give clients strategies that will help them be more consistent, effective and efficient, but there are limits to what we can achieve.  (This applies equally to my non-ADHD clients.)  The good news is that perfection isn't necessary.  Even a little progress can make a major difference in your life, self-esteem and relationships.  For example, your boss may be quite happy if, instead of being twenty minutes late to work twice a week, you can reduce it to being ten minutes late once a week.  You're not batting a thousand, but your boss may be flexible if you're doing well otherwise.  Or if you interrupt your spouse every five minutes, you might find him or her more accepting if you can limit it to once every ten minutes, especially if you are occasionally able to stop yourself and apologize.

 

Treatment goals like these are more attainable, and more motivating!  Although a challenge can be energizing, unachievable goals are demoralizing.  Sometimes, less is more.  Less lofty goals can help you give yourself credit for the progress you do make, and it puts you in a better position to admit your shortcomings but still stand your ground.  For example, you can tell your boss, "I know I'm still late more often than either of us would like, but I've been working on it and I'm doing better.  I'll keep working on it, but I don't know how much better I'll be able to do, at least all the time.  Besides, when I am late, I always make up that time at the end of the day."

 

Remember, people who don't have ADHD aren't perfect either.  Your mistakes and shortcomings may be more obvious or occur more often, but you're not the only one who blows it occasionally.  You don't need to be perfect to live up to other people's standards.  Every successful relationship depends on acceptance and compromise.  Just as you'll be happier if you cut yourself some slack, you may find you enjoy your relationships more if you cut other people some slack too.  Hopefully they will recognize it and return the favor.

Dr. Tuckman, a psychologist in West Chester, PA, is the author of "More Attention, Less Deficit: Success Strategies for Adults with ADHD" and "Integrative Treatment for Adult ADHD: A Practical, Easy-to-Use Guide for Clinicians."  Learn more, download Chapter 1 free and listen to his free weekly podcast at http://adultADHDbook.com.