well if re-education in england is anything like the usa, it fails for mainly one reason. when your labeled a criminal, or felon, you really can't get work. you end up only being able to work at a place like mcdonalds, and when your trying to go straight and narrow after years of crime and cant even make enough money to pay your bills much less feed your family, then its real easy to see why ex-cons slip and start breaking the law again, whether it be drugs, theft, fraud, ect.
re-education is only as good as peoples ability to have a chance of a decent life if they leave crime behind them, otherwise it doesnt work.