Why prevention is better than cure

Assume that you are a sociologist interested in examining the conduct of marriages. Would you think it sensible to proceed by focusing almost entirely on those cases of marriages which failed and went through the divorce courts? I am prepared to consider the supposition that the worst and the most acrimonious divorces are those in which the wronged partner went on suffering abusive behaviour of various kinds for many years before coming to the divorce court. But would that necessarily lead to