Actually, OCD is neither a lack of willpower nor an impulsivity problem.
If it were a lack of willpower, then a good lecture or a verbal thrashing ought to be plenty to get someone to just give it up and gain the needed “moral fortitude” to be fine.
If it were an impulsivity problem, then we would see impulsivity in numerous areas, not just in the compulsions that characterize a particular case of OCD.
OCD is a mental disorder that affects the deepest parts of a person’s brain. It is not something that can just be wished away or punished into submission.
It is, however, a disorder that can be treated, and people with OCD can learn to live healthy and productive lives.