More likely you got options, and they are taxed as income at a liquidity event (acquisition, IPO)... unless you were confident enough in the startup to execute

More likely you got options, and they are taxed as income at a liquidity event (acquisition, IPO)... unless you were confident enough in the startup to execute those options & immediately pay the resulting taxes out of pocket. And you have to have that confidence before the valuation is too high & the taxes are unaffordable to absorb.