No, a person does not choose to be addicted to drugs. What happens is that there are people who due to certain factors are more likely to be addicted to others. When a person consumes a drug, it does not do so to become addicted. Addiction is generated when it has a behaviour not appropriate to the substance ingested, where the person wants more and more regardless of how they get it. In the end, it is too late for the person to want to give up consumption on their own and will need help to do so.