Using French administrative data on job-creating entrepreneurs, I estimate a life-cycle model in which risk-averse individuals can start businesses and return to paid employment. Then, I use the dynamic model to value the option of returning to the labor market in case of failure. For new entrepreneurs, this option is worth 6.4 the average net wage in the country, which represented 136,000€ in 2018. This option value is explained by the unobserved heterogeneity in entrepreneurial abilities and the random-walk component of productivity. Estimated unobserved benefits of entrepreneurship represent 38.6% of the average net wage pre-tax per year (some 15% of profits), or 8,250€ in 2018. Unobserved benefits add up to 90,700€ over the average entrepreneurial spell. Together, unobserved benefits and the option value of returning to paid employment explain 42% of firm creations.