Quitting Smoking: Common Errors
"The biggest mistake smokers/tobacco chewers make when trying to quit is giving up. Did you start smoking or chewing tobacco in only one attempt? Very few people succeed at complicated tasks the very first time. The same is true of people trying to stop using tobacco. The bottom line is KEEP TRYING." Other common errors: jumping in without a plan, ignoring your uniqueness, quitting in secret, going it alone, believing you can have "just one", switching to low-tar cigarettes.
http://www.shpm.com/articles/atd/quitsmk.html.