Tobacco companies know it, and now it's been proven - it's incredibly easy to get addicted to smoking.
Around two-thirds of people who try even just one cigarette end up smoking at least daily, analysis of smoking data from the UK, United States, Australia and New Zealand has found.
"This is the first time that the remarkable hold that cigarettes can establish after a single experience has been documented from such a large set of data," said Prof Peter Hajek of Queen Mary University, who led the study.
The surveys looked at asked more than 215,000 people about their smoking history, and found somewhere between 61 and 77 percent of people who try a cigarette go on to become regular smokers, at least temporarily.
Prof Hajek says it highlights the need to stop young people from having even a single puff.
"We've found that the conversion rate from 'first time smoker' to 'daily smoker' is surprisingly high, which helps confirm the importance of preventing cigarette experimentation in the first place."
In the past 10 years, the percentage of Kiwi teens aged 15-17 who have smoked have dropped from 16 percent to 4 percent, and young adults aged 18-24, it's dropped from 28 to 20 percent.
The overall smoking rate for New Zealand adults over the same time period has dropped from 20 to 16 percent. Prof Hajek says some of that could also be down to the introduction of e-cigarettes.
"Very few non-smokers who try e-cigarettes become daily vapers, while such a large proportion on non-smokers who try conventional cigarettes become daily smokers. The presence of nicotine is clearly not the whole story."
The findings were published in journal Nicotine & Tobacco Research.