I completely agree with your point. Addiction is a very bad habit which is very difficult to quit once it is started. And for some people, they don't leave until they lose their lives. Even if they want to leave it, every time they do thinking that this is the last time.
Very true. They always tell themselves that that is the last time but the truth is that there really isn't any last time, because they will end up doing it again.
And that's why it's best to never start it in the first place. Not starting at all, is much more easier than trying to quit.