I joined a company which had already IPO'd, 1 year before I joined. And had had 14 years of its runway. They gave me some options, which would mature in 5 years. During that period, the stock exploded. Which the company founders, themselves never expected, else they would have given off much less to employees. Some other employees who had the stock matured, sold it.

They gave me stock options worth 300 $ but it increased 2000 times, in a span of 10 years. It increased so much, that I sold it eventually(to avoid all eggs in one basket). Got myself a house. Loan free. And started my own startup. Which I run till date.