There had been a number of attempts by the UN and OSCE to promote peace through diplomatic means, but the political will from key nations such as USA, UK, Russia, France, Germany had been lacking -- until now. In fact according to the Sunday Times, the CIA aided the Kosovo guerilla army4before the NATO bombing of Yugoslavia. And according to the following article, there have been a number of "humanitarian spies5" leading up to the Kosovo military campaign. This therefore again raises more questions about how sincere and committed some of the NATO nations were when pursuing diplomacy.
Most peace processes are a long, complex process6; one which has to carefully consider a variety of complex issues that affect each side involved. You can't just quickly enforce peace, expect it to last and then forget it, and then get out.
It appears as though NATO has not thought7 about a long term solution and just gone for something that looks like a result, perhaps without giving real peace options a chance8.
With the 50th anniversary of NATO and people questioning the need for NATO9, a seemingly quick resolution of the Kosovo crisis lends credence to the effectiveness of NATO in such scenarios. Because the long term rebuilding is taken on by the UN, they can easily be blamed if it is not happening ideally, and if rebuilding goes well, then that shows that NATOs actions were effective. NATO ends up in a win-win situation while the local population have lost out.