Too many people equate the end of a physical addiction and the end of a period of detoxification off of drugs or alcohol as the end of recovery, and due to this misconception, far too many people endure the pains of detox on many occasions.
What is detox?
To detox means to rid the body of the lingering physical metabolites of the drug of abuse, and although the time needed for this can vary with the drug of abuse, between a few days and a week is long enough for most of the symptoms to disperse for most drugs. True detox actually continues for months, as the body slowly adjusts to sobriety and regulates processes damaged through addiction; and some symptoms of long term withdrawal and detox can linger throughout these months(Detox symptoms of common drugs).
But detox is not treatment, and in fact during the days of detox very few people are in any real shape to learn the kinds of things that need to be absorbed for any real chance at sobriety.