It's more than just the waiting though, it's the uncertainty and the fact that you've got this capital tied up in an investment that you could have in another investment (i.e., go work somewhere where you simply get paid instead of get stock).
Using a 10% time-value-of-money discount, your stock options are only worth ~35% of their final monetary value when you first start out in the 10-year payoff case. That's not a 35% chance that you'll make something, that's the discount on what you do make. You still need to factor in the risk that you'll get nothing or a pittance, especially if we're talking early startup where the risk that you get nothing is probably somewhere in the 90% range. You don't have to come up with very unrealistic numbers in the current environment before you're looking at applying a ~95% discount to your hopes on what your stock options might be worth in 10 years.
(IMHO, working at a startup when you're young for some hard & fast experience, if you can afford it, is possibly still worth it, but at this point in 2017, early engineers should be demanding either cash or founder-level equity grants. An in-between grant that may pay out $100,000 in ten years may sound grand from the perspective of someone about to receive that payout, but from the front-end you should value it somewhere around $5K or so, and I wouldn't fight anyone who wants to pick numbers to push that lower. On an annualized basis, $5K is more like "a minimal raise" than a reason to work at a company.)
Using a 10% time-value-of-money discount, your stock options are only worth ~35% of their final monetary value when you first start out in the 10-year payoff case. That's not a 35% chance that you'll make something, that's the discount on what you do make. You still need to factor in the risk that you'll get nothing or a pittance, especially if we're talking early startup where the risk that you get nothing is probably somewhere in the 90% range. You don't have to come up with very unrealistic numbers in the current environment before you're looking at applying a ~95% discount to your hopes on what your stock options might be worth in 10 years.
(IMHO, working at a startup when you're young for some hard & fast experience, if you can afford it, is possibly still worth it, but at this point in 2017, early engineers should be demanding either cash or founder-level equity grants. An in-between grant that may pay out $100,000 in ten years may sound grand from the perspective of someone about to receive that payout, but from the front-end you should value it somewhere around $5K or so, and I wouldn't fight anyone who wants to pick numbers to push that lower. On an annualized basis, $5K is more like "a minimal raise" than a reason to work at a company.)