If you promise yourself you will not drink, but you do
If you promise your loved ones you will cut down, but you don't
If you are ashamed and guilty of your drinking, or you contine to drink when you have set limits, say two drinks tops....
well, those were the signs for me
No amount of willpower or moderation worked to free me from my depression over alcohol, the guilt, shame, suicidal thoughts, nothing worked but never picking up the first drink to begin with. I encourage you to read here a lot, to post, to realize though it seems scary to never drink again, in fact it is freeing and a wonderful habit to break.