Every demo you have seen was filmed at 22 °C
The pilot worked because the room was air conditioned. The rollout fails because the roof is not.
There is a specific way AI projects die in this region, and it has nothing to do with the model. The pilot runs in an office. The office is at 22 °C. Everything works, the numbers are good, and somebody signs off on a rollout.
Then the same hardware goes into a sealed enclosure on a roof in Jebel Ali in August, and the clocks come down. Not dramatically. It does not catch fire or throw an error anyone notices. It just runs slower, drops frames, misses the defect it was bought to catch, and everybody concludes that the AI was oversold.
Nobody films the failure. It happens in August, on a roof, eight months after the press release.
The arithmetic is not subtle. Every passive cooling path is proportional to the temperature difference it has to work with. Against a 90 °C junction limit you have 65 K to spend on a 25 °C bench and 42 K at 48 °C ambient. Same heatsink, roughly a third less capacity, and that is before you add dust to the fins or put the box in direct sun.
What makes this worth writing down is that the people selling the model and the people specifying the enclosure are almost never the same people, and neither of them owns the failure. The software vendor demonstrated the software. The integrator installed what was specified. The buyer is left with a system that works in March.
The fix is boring and it is available at the start of the project for a fraction of what it costs at the end. Size the thermal path against the ambient the equipment will actually see, not the one on the datasheet. We publish the calculator we use for this and charge nothing for it, because the alternative is another site that concludes AI does not work outdoors.