Added to the chronic lack of resources is the UN's curiously conciliatory attitude towards the Sudanese government. In many ways Unamid was damned from its inception, undermined by the UN's willingness to appease President Bashir, making cordial relations with Khartoum its priority.
Before a single soldier set foot in Darfur, the UN had conceded to Bashir's demand that his government would dictate the terms of deployment. Unsurprisingly, the conditions set by Sudan have been so unrealistic as to render Unamid ineffective. After removing Unamid's teeth, Bashir then delayed its arrival by refusing to provide land for bases, stopping equipment leaving ports, delaying visas by six months or more, and randomly imposing restrictions on movement. Why did the UN ever agree to ask the permission of the architect of a genocide to use UN planes to investigate reports of that genocide?
Unamid: UN/African Union Hybrid Mission in Darfur
Update: I've been corrected on the meaning of UNAMID - and given the following piece of information:
"That's also another massive hamstring for this mission. The African Union is a fairly pointless organisation that has been here since 2003, achieving bugger all. The UN realised that and proposed a joint effort, which saw UNAMID formed out of the old AMIS (African Union Mission in Sudan) on 31 Dec 07. The force structure is still very heavily constrained by the requirement to maintain a majority AU manning. The agreement between the UN and GoS (Governement of Sudan) means that no more thqan 10% of the entire force can be from "white" countries. This may be why the "European" contribution is mostly staff officers working at the Force HQ trying to untangle the mess that is growing as UNAMID gets closer to reaching the target manning levels."