The main draw of addiction is consistncy, I think. The cycle doesn't bring pleasure, pleasure is the booster rocket that falls off—no, the main pull of addiction, which keeps the habit in orbit, is predictability, balming the ever present fear of the unknown.
It is a near tautology: addiction is a loop, the sustaining force of addiction is that it is a loop and thus predictable. But this is a strength, not a defect, of the observation, for you'd expect the motivations for addiction to be somewhat circular since addiction is circular.
Also, there is independent theoretic basis to posit that the main drive of man and beast is to minimize marginal uncertainty—that's the free energy principle.
Precisely. In a sense it is compensating for an uncertain environment perceived outside by creating stable environs within, with the help of chemistry. And there is a dire feedback loop, much remarked, where drug makes your life worse & you use more drug https://twitter.com/DM_Berger/status/1234590269045137413?s=20