I've actually asked the question about shooting up before and the responses were what I restated. But I'd assume at that point it would have to do with the viscosity of whatever substance is going to be sent through your veins. If the material is not totally tired into finer liquid it would probably have more ramifications on your veins. I just think that most addicts who shoot up regularly prioritize getting their fix over properly preparing the substance before IV'ing it. Most addicts don't really have professional medical training or prepare the substances they're about to IV correctly. I don't know people who are on morphine drips as many times as an addict is shooting up heroin. At a certain point though, I really don't know and I'm just a stranger on the internet lol. I'd bet in Europe or places where heroin is allowed as detox treatment (iirc this is only in Europe right now) they have the diamorphine prepared as much as possible so there is such minimal damage to the veins. However, I have never heard about anyone complaining about hospital treatments causing vein damage from anything that they've been IV'd while under medical assistance.
I get what you're saying but I've never seen chronic meth use lead someone to a place other than darkness

I'd bet that higher quality meth causes less side effects, but it's unnatural to have that much dopamine released on a regular basis and eventually the brain would become ultra dependent on meth for mood stability. Anhedonia is definitely a long term side effect of heavy stimulant abuse. Tolerance is the enemy of addiction. Literally any addiction eventually within time results in something becoming "unfeelable," so you'd need higher and higher doses to get any effects and your tolerance just keeps escalating. It's good to take breaks if you can, especially with stimulants because diminishing returns is so fast for that class of drugs. Using stimulants on a daily basis inevitably causes tolerance to get sky high. There were one or two weeks where I was taking high dose adderall quite regularly because at the time my tolerance was starting to scare me. It was quite a miserable week and I stopped benefitting from using it at all. So when it comes to stimulants I just try to take 2 weeks off or more if I can. I mostly use pharmaceutical stims for recreational purposes over actually needing them to get work done. Stimulants in general are far more effective when you've let your brain regenerate some natural dopamine--which doesn't happen if you're using daily. If you look at the MDMA abuse threads the side effects of users lasts even years if not permanently. Some of these side effects include anhedonia, heavy anxiety, memory problems, etc. Stimulants can also turn you into an anti-social hermit as perpetual use can create social anxiety and paranoia. It's weird talking to someone while stimmed out and your mind is racing 100 miles per hour and they're completely sober. You start thinking that they're thinking thoughts they absolutely aren't thinking and become detached from reality. Out of any drug I know meth causes people to absolutely go bonkers and lose their saneness entirely. Probably from psychosis. The scariest part is that they never seem to realize how detached they have become and it's always
anything but the drugs that lead them to insanity.
I think people often forget that methamphetamine and heroin are harder drugs. The euphoria is light and in the beginning they always seem less devastating than the media makes them out to be. Problem is when you actually try to quit, the positive effects are so engrained in your life that it's such a severe struggle to cope day after day without them. In addition, the withdrawals are mentally quite severe to the point that the user is miserable. And not just for a week or so, it can take months to feel remotely even normal again. You only realize how powerful the drugs truly are when you try to become sober
and can't. It's not going to be fun anymore in a year or two. And you probably will get fed up with the quitting process and how difficult it is to just endure every second of a life without dopamine while your brain replenishes it's natural balance. No one wants to quit meth or heroin. They quit simply because they are forced to. You don't want to hit rock bottom. Get out when you realize it's starting to negatively impact your entire life. It's the opposite of fun when you repeatedly relapse just to feel baseline again. Pretty sure almost every addict has been there before.