Well I’ll tell you my experience and of some people I know. I used heroin so far maybe 30 times or so over time-span of many, many, many years. Never longer than a few days at a time. I managed to do so because of person I shared it with, caution to neither allow even glimpse of tolerance increase not to say WD, not really having it as a drug of choice (at a time my drug of choice was mostly some psychedelic and weed) and never getting myself into situation where I have any kind of stash. I would get addicted if I had enough all the time with me, I know it. I also never used it I.V.
Some other people I know who played or play with heroin and (still) didn’t fall into it’s jaws all have different stories. I met a guy who used a lot of it, for a long time and stopped when his life improved, he was addicted but stopping for him was nowhere near horror story you would expect from daily use of nearly pure H (only snorted it). I have a friend who would still occasionally use H, but isn’t satisfied with quality he can get atm, same friend gave his and his gf’s stash for someone to hold as soon as he felt their use is spiralling out of control. I have a friend who used H for 3 months, stopped and ever since rarely uses opiods at all, person he was using it ended using I.V. for many years. I have a few friends who only ever used or still use it just on very rare occasions. Like people mostly using drugs beside weed only on festivals, they so don’t mind in such occasion getting heroin (or opium). Are we all still destined to be really fucked with opiods (I had my share with morphine but surprisingly stopping it was a peace of cake compared to benzos), idk, can’t see that happening to everyone I mentioned.
What’s more important for every person I mentioned I met at least a few who ended up in a very bad relationship with H (I’m talking only irl to not complicate it) and I can tell you what’s common for almost all of those, I.V. use! Not a single person I know who got by relatively unharmed with H used it I.V., not a single one. Another thing common to those rather unharmed is that most of us, certainly significant majority of us saw what H can do to a person and have/had addicted friends, one thing is reading about it and another thing is first hand seeing how H creates a crooked or sick addict out of great people. That’s a thing in my country, after and during war many, many people got addicted to H and on the other side you mostly had folks really hating addicts or at best fearing them or feeling disgust. When H fall out of popularity (some died, some went in rehabs, some got to maintenance, some got busted, more other drugs got winder popularity etc.) new breed of users from mine and generations around mine was a lot more careful and never could have looked H trough the pink eyeglasses like some before us did.