COP30 in Belém was billed as the implementation COP.
It was supposed to focus on getting countries to deliver on the commitments for climate action they signed up to in the 2015 Paris Climate Agreement and the eight subsequent COP negotiations that followed, before this one.
With global warming already above the Paris Agreement limit of 1.5 degrees Celsius the need to reduce or "mitigate" greenhouse gas emissions, to limit the rise in global temperatures could not be more urgent.
But mitigating greenhouse gas emissions is a very hard slog. It requires system wide transformations in energy and transportation. It is disruptive, expensive, takes a long time, and is not easy to do. Yet it is the only way to contain the rise in global temperature.
So, when COP30 was labelled the "implementation COP" by President Lula of Brazil and the UN, it was natural for people in this part of the world to expect it would conclude with a strong commitment to crank up climate mitigation measures.
Two years ago, at COP28 in Dubai, the entire world agreed to start to transition away from fossil fuel usage - an enormous achievement for negotiators at the time.
Transitioning from fossil fuels to renewable and clean energy is the most important climate measure of all. There was no follow up or mention of that commitment last year at COP29 in Baku.
But at COP30, given the urgency of the climate crisis, and the well flagged focus on implementing previous commitments, the most important thing was to put flesh on the bones of the agreement to phaseout fossil fuels.
That is why Ireland, all EU countries except Italy and Poland, the UK, Columbia, Panama, and many more - 85 countries in all - went hell for leather to get a "roadmap for transitioning away from fossil fuels" into the final agreement.
Of course they have failed to achieve that, blocked by an equally large group led by the Arab oil producing nations and Russia. Their attitude throughout the COP30 negotiations was one of "hands off our oil".
The primary focus of many developing nations, particularly in Africa was very different to that of Europe.
They are on the frontline of climate change, often suffering the most devastating consequences of extreme weather events and climate disasters.
They are not responsible for the greenhouse gases that have driven climate change, and they don't have access to the financial resources needed to protect themselves, adapt, or even recover after extreme weather events.
So, when they thought about the COP30 being an "implementation COP", the thing they were most desperate for is to have the $300 million per year of climate finance promised by wealthier nations start to flow.
A Loss and Damage Fund to help recover directly after climate disasters was agreed and established two years ago, but where was the money for that.
It took 12 years for the wealthier nations to achieve a separate goal of ensuring €100 billion in climate finance for poorer nations, yet only a fraction of that money flows their way.
Then there is the need for separate funding for climate adaptation in poorer countries. As much as $40bn per year was supposed to be set aside for that last year. Where was that money? It needs to be four times larger and when is it going to flow?
These were the promises that many developing countries wanted implemented first and foremost at COP30.
The idea of signing up, at the behest of wealthier nations including the EU, to having the type of fuel they could use to grow their economies restricted, while those richer nations fail to deliver their financial promises was never going to fly for them.
It is a key difference of perspective about climate change that the Arab oil group along with Russia was well able to encourage an exploit at COP30 to block any mention whatsoever of fossil fuels in the final text.
This difference of perspective underscores just how complex it is to achieve a multilateral consensus about what the "right thing" to do is when it comes to climate action.
Read more:
Compromise deal at COP30 sidesteps fossil fuels
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