It's wrong to lump all alcoholics together and judge them. I haven't had a drink in 23.5 years and got sober on my first try. Some alcoholics don't want to be/stay sober. Some are too self-destructive to stay sober. The only thing I know is that no one can predict who will drink again and who won't. It's impossible to predict that, even for so-called experts.
Years ago I realized that the meetings I've been going to for so many years don't get any bigger. With all the newcomers we should be in Yankee Stadium by now. And yes, sure, some people move, but these meetings should be much, much bigger. Maybe it helps to realize that alcoholism/addiction is a mental illness.
The reason is that most people don't stay sober. For whatever reason.