You should understand that different drug delivery methods will have different impacts on a drug's half life and effect (intensity) on your body. Inhaling is more powerful than taking orally. Shooting up is more powerful than inhaling.

Inhaling cigarette smoke is an almost instant intake of nicotine. Vaping it is not nearly so. It’s still an open question as to why, but the current thought is because the atomized liquid droplets are much, much larger than the smoke particulates that come from burning tobacco. The atomized liquid doesn’t make it into the alveoli where it directly enters the bloodstream. Instead, the vapor coats the bronchial and nasal passages and is slowly absorbed that way.

There’s still debate as to whether the bulk of the nicotine is even absorbed in the lungs vs. deposited vapor in the nasal and oral mucosa. But whatever the route, vaping is significantly slower than smoking—something that a lot of “switchers” don’t appreciate. (They don’t get the instant gratification that they did when taking that first drag off of a cigarette.)

I don’t mean to refute your point. The hierarchy of drug intake is legitimate. But vaping is more like “inhalation*” with an asterisk. Maybe faster than a lozenge or patch, but definitely slower than smoking it.

Well no, vaping is more addictive because inhalation as an ROA is more addictive. This is a well studied effect.

On the other hand, I would say smoking crack is much more addictive than snorting cocaine but that's just my opinion. Maybe someone with more exerience could weigh in?