I can't think of any serious initiatives that the UN has launched in the past 20 years that has ended well, as some of them have even been downright destructive (UN relief to Haiti, Srebenica ext). The organization is grossly inefficient, many of the official charities (UNESCO) are horrible returns on investment, some of the UN's most highly publicized and valued institutions such as the Human Rights Council is a complete and utter joke given the fact that it's members tend to be from the world's most repressive regimes. There is little in the means of budgetary controll for the UN, as every nation gets an equal say, yet only a small percentage of nations even pay ANYTHING towards the UN's upkeep costs. You'd think the US, who provides a substantial portion of UN funding and their HQ, would at least get a higher say in regards to budget matters but nope, they do not, leading to spiraling and out of controls cost runaways.
And of course, the most obvious flaw of the organization: the only part with real teeth, the Security Council, only works when all Great Powers agree on an issue. Thus, the security council is of limited use in almost all important matters.
The UN, dont get me wrong, has had some successes but most of these are not through UN direct efforts: the millennium development goals were maybe written up by the UN, but private charrities and governments did most all the heavy lifting.
