I've never smoked, but I've been around people that do. What do people feel during/after smoking? It doesn't seem to make people high or hallucinate or anything. It maybe mildly relaxes them?
When I was smoking I found that they enhanced the effects of other drugs. Since it's a stimulant it keeps you from getting sleepy when you're drinking or smoking weed. With coffee I found it smoothed out the jitters and let me work a lot longer without needing food.
That being said, the constant stink on my clothes and the huge price of cigarettes got me to switch to vaping, and I'm reducing the nicotine concentration to help me kick it entirely.
From experience, once you're genuinely ready to stop and you're already down to 0mg, at some point you'll just randomly get too lazy to change your coil and that'll be it.