> If people don't learn that poor decisions lead to poor results, then they will continue making poor decisions.
In the context of this specific story, it seems to me that Jack was perfectly well aware that his decisions were leading to "poor results" and would continue to lead to poor results, and in general my experience has been that addicts are usually aware that their addiction is ruining their life.
The thing that's not clear to me is to what extent making the consequences of addiction _even worse_ effectively provides additional motivation. In particular, people's subconscious often seem to do a really bad job of making decisions where all there are no "good" outcomes available, and the magnitude of the differences between the bad options doesn't influence that much (see the trolley problem).
If you believe that people's decision making is heavily affected by the difference in magnitude between the bad options, pushing for harsher penalties and consequences for addicts seems promising to help solve the problem. If you don't believe that, it seems like just causing unnecessary suffering that won't actually help.
Personally, I suspect the _type_ of consequences matters a lot, with immediate pain/pleasure influencing motivation very differently than long-term intellectual consequences. I wonder if heroin laced with capsaicin would be useful.