The tradeoff for the bad hours/pay is that you'll get more autonomy in your work and the ability to really influence the product. To me, this is why you should work for a startup. Certainly not for the stock options.
I'm beginning to really hate hearing this over and over. So many people accept this at face value when in reality it's dubious at best.
Case in point: 6 months ago I left a start-up for a medium-size company (~300-400 people) that has been around for ~15 yrs with no ambitions of going public nor taking outside investment. I get both amazing pay and an insane amount of autonomy. I doubt this could be matched by a Big or Small company.
Here's the rub: Silicon Valley markets itself VERY WELL and if you're willing to internalize everything that comes out of this marketing machine, then yes... it's snake oil.
I'm not diminishing the the importance or impact of entrepreneurial ventures, but I think we can do better than Cookie-cutter Generalisms repeated ad nauseam without independent thought.
You also need to factor in that start-ups pay generally a below-market wage, and often do not have benefits on par with other employment options.
For a long time, the standard argument has been that you should view the expected payoff of the equity as a form of offsetting compensation. If your salary is X-thousand below market, but under average-case circumstances your equity is worth Y-thousand-per-year, and Y == X, then, in theory, you should view the offer as exactly a "market" pay rate. Of course there are also effects of being forced to defer compensation to the future, deal with tax implications, and potentially also be compensated for risk of failure, and so forth, so Y should actually have to be significantly above X, but the general idea is the same.
If you view the equity as lottery tickets (and I agree that you should), but you also accept a below market pay rate, or bad benefits (like an onerous regular premium for insurance, or the absence of a company matched 401(k), or extreme working hours, and so on), then you are basically doing nothing but accepting a job for below-market pay, without getting a single thing as a compensating benefit in return.
You are literally doing nothing but devaluing your own labor and by sending the market signal that employers are capable of hiring you like this, you are also contributing to driving the price of labor in your field down overall too, which could hurt your peers and your future self.
There are often further negatives about start-ups too. For one, they often try to cram you into low-productivity open-plan offices, but then turn around and try to defend it with buzzwords about teamwork and company culture. In some start-ups, your visible enthusiasm for the arbitrary workplace choices of the management is also a component of how you are evaluated. If you're merely neutral about something like, say, dog-friendly offices or frequent alcohol-focused gatherings, as opposed to being visibily excited about them, this often is held against you when it comes time for raises or promotions or, more often, layoffs.
Many start-ups don't really think for themselves either. They use management processes like Agile/Scrum because it gives management a convenient fiction that the company's development work can be commoditized, and that they can hot-swap new employees in at any time. They are notorious about not doing proper capacity planning or planning around an engineer's specialties. You might have been hired because you're great at front-end work and then end up spending 100% of your time migrating customer data from MySQL to Postgres. Or you might be a mathematics / statistics worker and spend all your time making web applications in Django. It will all be covered by catch-all excuses about the company pivoting or you needing to wear lots of hats or some bullshit, and if you raise any discontent over how much disrespect is being shown for your specialty or aptitudes, it will be ignored or punished.
And after all of this, the best case scenario, which is exponentially unlikely, is that you'll make a small amount of money from your stock options (assuming you saved enough from your below-market salary to actually exercise them), which still won't be enough to buy a house in the Bay Area.
I'm not saying start-ups are tautologically bad places to work. It would be great if at least some of them began acting as responsible employers. But, you really need to deeply consider a lot of this stuff before choosing to work for a start-up, and really have a clear understanding of what other benefit you are getting (maybe your significant other lives near the start-up and you don't need money or respect at work?).
The fact that so many people accept these bad working conditions is our own fault, as a community of developers, and until more engineers (especially younger ones) start to stick up for themselves by boycotting jobs that infantilize them, we have only ourselves to blame for the horrendous working conditions we're made to accept.