What is the pro and cons of the United Nations? then come to the conclusion: Have UN done more harm or good?

So give me good arguments and draw to the conclusion. have the UN done more harm than good or not? tell me please. List of events that UN tried to intervene and failed and/or suceed. Like Saddam violations of 17 UN resolutions for example. Shroud we keep it or kick the UN building out of NY?