0DTE Options, Explained Without the Hype: The Mechanics, and the Honest Risk
Zero-days-to-expiration options are the most hyped and least understood corner of the market, now nearly half of all S&P 500 options volume. This is the straight version — how extreme theta decay, the gamma spike near expiry, and raw leverage combine to swing a 0DTE option violently on a small move in the underlying, which is exactly what makes them the highest-variance instrument most retail traders will ever touch. And the part the hype leaves out: on the research, retail buyers of 0DTE options lose money on average.