AI Is Hitting the Sweet Part of the S-Curve

One of the most compelling theories about the future of artificial intelligence comes, oddly enough, from a 161-year-old paper about the coal industry. In 1865, the English economist William Stanley Jevons observed that improvements to the coal-fired steam engine had not reduced Britain’s coal consumption. Instead, they had massively increased it. Improved efficiency lowered the cost of steam power, which created so many new uses and users that total consumption skyrocketed. This became known as the Jevons Paradox.

Microsoft CEO Satya Nadella invoked it after DeepSeek launched its low-cost AI model early last year, and the numbers bear him out. According to Epoch AI, the price of running a large language model at a given performance level has been dropping at a median rate of 50x per year. And yet OpenAI’s annualized revenue went from $2 billion in 2023 to more than $20 billion in 2025, while its computing capacity tripled in a single year. Costs are collapsing. Spending is exploding. This is the Jevons Paradox in action.

Most efficiency improvements don’t trigger this kind of explosion. LED bulbs became radically more efficient, for example, but there are only so many rooms to light. Internal combustion engines improved steadily for decades, but people don’t drive twice as far just because their car uses less gas.

AI is different. The question isn’t whether the Jevons Paradox applies — it’s when.

The answer has to do with how technologies spread. As McKinsey’s Richard Foster showed in his 1986 book Innovation: The Attacker’s Advantage, technologies progress not in straight diagonal lines upward, but in S-curves: slow adoption at the bottom, explosive growth in the middle, saturation at the top. Sail gave way to steam. Vacuum tubes gave way to transistors, which gave way to semiconductors. Each followed the same pattern.

The critical moment is the inflection point where the S starts to go vertical. Call it the hidden threshold. Below it, the technology works, but it is limited to elites. Only the people with enough money, technical skill, or institutional access can use it, and they kludge their way in. Hedge funds were paying for custom natural language processing tools years before ChatGPT existed. Software had access to GPT-3starting in 2020. The technology was both powerful and restricted.

When well-resourced insiders are spending real money to get access to something, that’s a tell. Demand is lurking, waiting for the technology to become accessible enough.