There is some evidence in the scientific literature to suggest that cannabis has a low risk profile for addiction, with lower rates of addiction in regular cannabis users than in users of alcohol, tobacco, and even caffeine.

Reference: Anthony JC, Warner, LA, and Kessler RC. Comparative epidemiology of dependence on tobacco, alcohol, controlled sub¬stances, and inhalants: basic find¬ings from the National Comorbidity Survey. Experimental and Clinical Psychopharmacology 1994;2(3), 244–268.