Instead, I think it needs a another column for additional gross income for purposes of tax liability in year of liquidation. As I understand it, when you exercise your options at $1.20, you must pay $100k to exercise, then you own taxes on the $20,000 in gains. When you exercise at $20, you must again pay $100,000 to exercise the options, and also pay taxes on the $1,900,000 in gains.
And this fact is what causes early employees to walk away from so much money. There's a huge difference in viability of paying the tax bill on $20k of income vs. $1.9MM when the underlying assets are illiquid, and cannot be sold in part to cover the bill.
Most people will be able to come up with another $6,000 or so to cover the taxes from an early liquidation. But it's substantially more difficult for most to come up with the $500,000 to cover the tax liability in the second case.