The Citadel Paradox: Why Ken Griffin is "depressed" by AI, but still only hiring humans

The hidden flaws of AI-generated trading code, the latency bottleneck, and why the human quant is far from extinct.

Dear Reader,

In May 2026, Ken Griffin, the billionaire founder and CEO of Citadel, stood before an audience at the Stanford Graduate School of Business and made a startling confession [1].

He admitted that he went home on a Friday “fairly depressed” after watching what agentic artificial intelligence could do within his own firm [1][2].

“To be blunt, work …