Yes.
This is one that thought of but forgot half way through writing my post. (You'd think with all the essays I've ever written I'd know how to write a topics list before beginning the main verbiage first). I agree this is one that is definitely a factor and goes under the Habituation topic. In the zenith of my smoking days (while in A'stan), we'd watch movies all the time as a diversion. Someone would light up a smoke in the movie or show we were watching and immediately I'd get the desire to light one up. What's worse is when that trigger still happens after you quit. When I see that I sometimes still think about it and immediately start looking for my vape kit. Although I'm finding that trigger is starting to wane.
Stress is another, (the destructive mentality should be a subtopic of it now that I look back). Stress can cause us to run on a thought process that is subconscious. So many people equate smoking with stress relief that the brain instantly goes with what it knows. Sometimes picking up a smoke can be a near involuntary act if you run on automatic. The longer you do it, the harder it probably is to get rid of that.
Non-supportive peers - My best friend who loves me to death, still tries to offer me smokes. Even though he knows I've quit. Not wanting to insult someone can be a factor in the flip flop, especially people you care about.
I think the ultimate one that I had to look at is...
Addictive personality - This one probably goes without saying. For some of us, we know limits and know how and where to keep our addictive personality from being too dangerous (like alcohol, drugs, etc). Others don't and smoking is nothing but one of the long list of addictions they need help with. I have an addictive personality, it was a hard hard thing to come to terms with. Which is why a flip flop on smoking can be difficult, because once you start up again, its just in your nature to power through and keep doing it. Of all the things my addictive personality is attuned towards, smoking is probably the one that offers the most options. I'm actually glad vaping exists because I'd rather be a vape addict than the alternative. There aren't many options for adrenaline junkies with a penchant towards combat zones. You get the idea. When I find something I like, whether harmful or not, my very personality compels me to stay at it.
Really great info, and I see a lot of points that you hit right on the head, as well Jman8. Really great insight!