Well, this is a tough one to answer
I tried many times to "moderate" and to quit. When I was 27, I managed to stay sober for a year. Here and there, I'd stop for a few days and a few weeks at a time. Six months a couple of times.
Then I joined SR in 2011. I drank again, and didn't quit for good until April of 2013 (age 35).
The final result of all the years of drinking (about 15 years total) was that I had come to a place where I fully accepted I could no longer handle any amount of drinking. Not one drop. Ever.