It is enough to understand the mechanism of dependence. Gabor Mate opens it perfectly. People are trying to fill the void with their addiction ....
There is a hereditary predisposition - this time. And there is a "risky" lifestyle, favorable for the formation of addiction - for example, there are few interests, social skills are undeveloped, severe stress, etc.
Most likely you mean why some will drink and look decent, while others, especially those who are close and dear to you, are really quite straightforward. Because it always happens. Strangers may or may not drink, but yours will bother you in any case. Some are not much different from others. Both are dependent. Scientifically, their body slows down the natural production of alcohol, but each in its own way. Someone faster, some later, but will have to "catch up, supplement" this deficit. And the time that a person can not drink depends only on his desire, will.