[jstanley]

Sure, you can get fired. But that just means you're not earning any more. You're not losing the money you already had, like the investors did.

[Paul-Craft]

Just to continue the analogy, an employee's monetary down side is limited to the amount of their investment, which is $0, modulo ESPPs and such. Investors can be leveraged and end up losing a multiple > 1 of their initial investment.