The meth puzzle

Of all the dangerous drugs that people try, I've always had the greatest difficulty in understanding why they would use crystal meth.  Surely there has been enough media exposure about the psychosis and vile bodily effects an addiction to it can have.

In the Saturday Paper, there's one guy's story of how he started using it, starting getting psychotic, but managed to get out of the scene.  The details are very common to what we've seen on current affairs programs over the years, and this was an apparently smart enough guy who thought he could try it safely.

I would assume there is research on the topic, and perhaps I should go looking for it.  But my guess would be that two factors are probably important:  first, he "gateway effect" of using other drugs such as marijuana and (I would guess) ecstasy, for which there is much less risk of addiction but pleasant enough experiences which lead people to believe they can upgrade to the next experience and also deal with it safely.  (I find articles such as this one which dismiss a gateway effect as illusory to be unconvincing and too pedantic.  To say a drug is a "gateway" is not necessarily an argument that is directly causative of further drug experimentation, but rather that its use sets the scene for experimentation with reputedly dangerous drugs by encouraging the rationalisation of their potential for safe use  I guess that the illegal status of the softer drug may help that rationalisation - by developing skepticism that illegality is motivated by the dangerous effect of drugs.)

Secondly, the social encouragement of other experimenters that they have not been hurt by its casual use, and can control how often they use it, must surely be important.  But given the clear, dire effects that it does have on so many people, how do so many first timers manage to not know of people in the same circles who have been sent over the edge by it?  As the author of the Saturday Paper article writes:

I was plainly ignorant about the drug before I succumbed. I’d considered myself a drug-savvy streetwise person before the autumn of 2014. However, my quick and doe-eyed plunge into addiction suggested otherwise. I had a number of key misconceptions about the drug: that meth didn’t kill you, that there was a safe level of use, and that meth didn’t do permanent damage.

What I find hard to credit is that any half reasonably educated person doesn't know of its dangers.  (Or can still rationalise experimentation despite knowing of them, I guess.)

Update:  OK, there have been a series of articles at The Conversation about meth use, and one claims this:

However, the majority of people who use illicit drugs do not use regularly or in large quantities. A relatively small proportion (for methamphetamine, around 10-15%) of users go on to become dependent and need treatment.

On the other hand, another article by the same author links to this study, which notes:

The estimated number of regular methamphetamine users in Australia was 102,600, or 10.3 per 1000 persons aged 15 to 49 years. Of these regular methamphetamine users, it was estimated that there were 72,700 dependent methamphetamine users, or 7.3 per 1000 population aged 15-49 years. The bulk of regular and dependent methamphetamine users were located outside of Sydney (83% and 80% respectively).

So that indicates that about 70% of "regular" users are dependent?

That puts the addiction picture in a much stronger light than saying that "a relatively small proportion" of meth users go on to be dependent*, but I suppose it could also means that relatively large number of people could only try it once or twice and not get further into its use?

*  can you imagine the situation if the number of regular alcohol users said to be dependent on it was 70%?