I read somewhere that everyone has a different threshold at which they would become addicted to coke. Some people could use it once and get hooked while others could use recreationally and not have a problem with it. The thing is- each time one uses coke, they get closer to that threshold.
The risky part is that no one knows how close they are to the threshold until they cross over that invisible line and become addicted. Cocaine is a dangerous and deadly risk-- it is better to leave it alone.