Joys of the Alternative Minimum Tax. The difference between the exercise and the FMV counts towards your AMT income.
(Disclaimer: not advice of any kind)
(Disclaimer: not advice of any kind)
1) $1m in cash
2) $1m in stock
3) an option grant to buy 1m shares at $0.000001. Each share has a FMV of $1.
Without AMT, you could always take (3) and they would get $1m of stock for $1. Tax free.
The difference is that they wouldn't be taxed until the gains were realized not when they were imagined on paper.
That gap between strike price and FMV is much more like compensation than it is an investment.