
Why is the effective strategy not moderation but absolute abstinence?
Therefore, each gambler must independently come to this difficult decision that gambling is a difficult path to restore lost money and rather easier to give up this with an uncontrollable addiction and earn money at a regular job.
If we follow the logic you described, then the gambler is trying to quit gambling, which means something has happened to him: problems or a big loss, and therefore there is no need to have false hopes for self-control if it has been broken.