This paper investigates whether managers fully incorporate the implications of their prior earnings forecast errors into their future earnings forecasts and, if not, whether this behavior is related to the post-earnings announcement drift. I find a positive association in consecutive management forecast errors, suggesting that managers underestimate the future implications of past earnings information when forecasting earnings. I also find that managers underestimate the information in their prior forecast errors to a greater extent when they make earnings forecasts with a longer horizon. Finally, I find that, similar to managers, the market also underreacts to earnings information in management forecast errors, which leads to predictable stock returns following earnings announcements.