What Is the Mythical Man Month?

Martin Casado says the mythical man month means you cannot increase the speed of engineering by adding people. The effect is very sublinear, like a natural law, because extra people add organizational communication. One author laid it out in the 70s. Software projects that were meant to ship faster went slower once more people were thrown at them. Engineering has always been the bottleneck.

Ten years ago, five founders who asked for a billion dollars and got it would have left the money sitting there or hired a bunch of engineers and detonated the company. He spent 10 years on a startup that became a very large business, and the limit held: engineering does not scale, so capital could not be thrown at the work. The biggest shift, at an industrial revolution level, is AI. A team of 20 people can be given a billion dollars and use it. Whether they make 500 million from that billion or two billion is unknown. The new part is that the money can be used productively. Anthropic and OpenAI have probably raised more money in aggregate than the entire downstream ecosystem combined. They turn money into growth.

Capital markets still have to figure out how to supply money on that scale.