Why is it hard to quit smoking? :what do you think it depends most on psychological or physical? why? -
Primarily physical, if you are talking about cigarette smoking.
Cigarette companies use ammonia in their process, so that cigarettes essentially -free base- the nicotine into your system. This is why cigarettes are so much more addicting than cigars or chewing tobacco. Even though tobacco has the potential to be habit-forming, cigarettes have been specially designed to be addictive, with over 50 years of research into how to hook smokers effectively.
2 reasons, smoking is a habit. after a meal, talking on the phone, after sex.. etc.. this is the hardest part of quitting to overcome. Second is the craving for nicotine. It is the hardest addiction to conquer.