At least with cigarettes, it takes 2 - 4 years to really cement your addiction.

Plenty of younger people (well I guess it's with juuls now) tell themselves they can quit whenever they want, and take break during a week of family vacation. No problem, so they keep on smoking.

5 years later when they try to quit they realize that maybe they weren't as bulletproof as they thought. I know for sure it happened to me.

Of course caffeine could be totally different addiction wise, and thankfully not nearly as deadly, but just some food for thought.