What does being "predictively inaccurate" mean in the context of the stock market? I assume that any time a stock jumps or falls is a symptom of inaccuracy--inv

What does being "predictively inaccurate" mean in the context of the stock market? I assume that any time a stock jumps or falls is a symptom of inaccuracy--investors were surprised by some previously unknown--and unpriced--event. So the low volatility of the stock market would indicate that it is actually predictively accurate, and that it is getting more so. Then again, volatility is kind of a silly measure, because we also care about the frequency domain. The market could be very good at predicting the very short term or the very long term or both. I wonder what a Fourier transform of the market would show?