For Clark, the solution is for states to back off and give the UN leader the power to act.
For example, five nations have veto power in the UN, which can hinder effecting action on peace and security, "even when an overwhelming majority of the Security Council and member states wants it".
In her opinion piece, Clark outlined the changes she believes the UN must undergo to effectively solve world crises the way it is meant to.
According to the former NZ prime minister, the UN needs to move to fairer representation on the Security Council (where places like Europe are over-represented, while others deserve more representation).
"On top of that, the requirement for a range of key agreements to be reached unanimously is holding our world back," she adds.
Clark points out the climate negotiations in Bali in 2007 which required a unanimous agreement. This meant that a "minority of dissenters" made it impossible to reach an important deal.
She also advocates for more power for the UN Secretary-General (currently former Portuguese Prime Minister António Guterres).
"Then there are the many constraints placed on a Secretary-General's ability to lead. The secretariat is subjected to micro-management by member states through various committees of the general assembly. There is little appreciation of the need for a clear line to be drawn between management and governance," she added.
For Clark, if these measures aren't taken urgently, the UN runs the serious risk of becoming irrelevant.
"If steps like these aren't taken, the UN will continue to diminish in relevance. The world needs an effective UN. The current limitations on its capacity to lead and act need to be addressed urgently," she concluded.