This article theorizes how short-term revenue volatility affects new venture viability and how such volatility develops over time. Tracking the bank accounts of 6,578 new ventures over a 10-year period, we find that, even after controlling for a range of other factors, short-term revenue volatility is a strong predictor of venture exit. Although short-term revenue volatility is associated with the depletion of buffer resources and financial default, surviving ventures do not, on average, decrease their short-term revenue volatility over time. However, short-term revenue volatility decreases at the cohort level due to higher exit rates of volatile ventures.