My interpretation of why this worked is, that from previously failed attempts (2 or 3 maybe), I had changed too much, and thrown away the packs and lighters.. I'd suddenly sit and think "that car.. it really needs refueling RIGHT. NOW. don't it?" and I'd drive to the gas station and when paying for gas, I'd say, as is tradition "and a pack of north state and a ligther please".. Brain finding a million excuses to go out and having to resist at those weak moments, was hard..
But having the pack always there made it a constant active choice of lower intensity rather than a more intense recurrent impulse.
Quitting is not a result, it is an effort you make through your life. It can be pretty easy for some, others need to focus a bit more. Build a strong determination to quit and have a positive outlook on life and your decision. The latter drastically affects how you experience cravings.
It becomes natural after a while, but if one can start smoking out of nowhere, starting this habit again is not less probable. Quitting is a continuous effort, but it is worth it.