Why do startups want their employees to work long hours?

Startups by definition are rarely profitable, so money is tight, and adding new employees can be hugely expensive in many ways (recruiters can charge five figures for a new engineer, training new employees is expensive, incremental overhead for a new employee versus others working harder is nontrivial, etc).  So, for better or worse, early-stage employees in a startup will work long hours, typically more for stock than for salary.  Fairness is no more relevant in the startup world than it is in a gambling casino: if the company is a hit, the early-stage people may be set for life.  If not, you have a bunch of paper and hopefully a T-shirt, and at least useful knowledge and experience for your next gig. That said, some startup founders take the work-till-you-drop culture to extremes, and companies that develop this sort of culture aren't all that great for employees with families and children unless you're one of the principals (and willing to make the large personal sacrifices to do this sort of thing). If you aren't one of the founders, you need to figure out the culture of the company and make sure it fits with your work-life requirements before you join the company as it's hard to change once you're there.

This is a side point, but it's a dangerous myth that all full-time salaried employees are exempt from overtime pay requirements in the United States.  Under federal law, whether or not a salaried employee needs to be paid for all time worked beyond 40 hours in a week depends entirely on the nature of that person's work; only a few limited classes of work meet the exemption requirements.  The most commonly exempt worker types are: Corporate executives Administrative employees Learned professionals Certain computer professionals, including programmers, systems analysts, and systems designers; most helpdesk support personnel, technicians, and systems administrators/operators do not qualify for this exemption. Outside salespeople (traveling salesmen) Highly compensated white collar workers (total compensation of over $100,000 per year). Some states have even more stringent laws, requiring that nonexempt workers be paid overtime for all time worked in excess of 8 hours in any single day. That said, many business owners either don't know or don't care about these laws, but that can come back to bite them in the ass if it's later determined that they should have been paying overtime all along, resulting in thousands of dollars in back wages and fines that have to be paid out.

they want long hours because they just want to get their company up and running as fast as possible. also because at the beginning of the company there is a lot of things to do right. every time you need to fix little glitches. the faster a startup takes of,f the higher chance it has to become successful. thats why they need to put in ong hours, and a lot of times they dont pay. check out the website http://www.sproutr.coif you want to talk to entrepreneurs from all around the world

I think that the question is a bit of a generalization - not all startups  necessarily "want" or "force" their employees to work excessively long hours. This is my third startup and third time as CEO, and I've always believed in open hours - it is up to my staff to decide when they want to work. Of course, 9 AM to 5 or 6 PM is the "norm," but if they chose to spend more time in the office, it is because they enjoy the work, they are passionate about what they do, and they are invested in seeing the company do well. I don't "require" them to stay here any longer than they want to, and for their part, they get all their tasks done, whether it is during "normal" hours or during "extra" hours (at which point, it is by choice). If you have a boss who is "forcing" you to do more work than you can handle or than you want to do, I think you can just let him know that, while you respect the breakneck culture of startups, you, for one, would like him to respect your personal needs. Just keep in mind that though startups may generally have longer hours by virtue of their business model, it is not holistically true with all startups, and that moreover, overtime is often a choice made by employees who are particularly dedicated to the company.

The why has been already answered. The what is tricky and more or less depends on the specifics. At the end of the day though, the solution always converges to a single one - set up your personal priorities. Evaluate your situation, identify your priorities depending on all externalities and stick to them, firmly. Then, if you have to argue with the CEO, do it. If you have to quit, do it. If you have to sue them for legally breaking your contracts, do it. You should stand your grounds and not deviate from your own principles manifested in the chosen priorities. People are different, objectives are different, lives are different, so why should you be bound by what a start-up - a corporate entity led by a subjective human being - wants you to do? You have to make the impression that you know what you want, how you want it and why you want it. Your confidence in knowing your own desires and firmly sticking to them is what will differentiate you and what will (presumably) solve the long-hours problem. For example, if you have X stock and Y salary and T time and N activities you like doing, you should be able to redistribute portions accordingly and rank them; say that your own nature tells you that you must have at least 20% of T for activities outside of work (#1) and that the particular X+Y combination cannot take more than 64% of your T (#2). So, you have a first-order approximated solution - you cannot work more than 10.24 hours a day for these given benefits (assuming 16 hour day). But if you have a X+x and Y+y combination, this may go up to 11 hours. But this may be in a contradiction with a higher-ranked priority (#1), so it immediately becomes a no option (or a low probability option). And so on. The important thing is given the initial data and your principles to set up a concrete framework of priorities that you feel confident about. If quitting is not a part of your solution, that means that quitting should not be placed in your priorities (or could with a low rank and minimal fraction/probability) or "not quitting" should be placed high in your priorities list. You always negotiate low-ranked priorities first and almost never want to negotiate the highest-ranked priorities. Have everything laid out and logically connected and be open to a detailed, constructive discussion with the start-up decision-makers. Remember, people are different and one-to-one comparison is hard to be drawn unless ALL of the variables X, Y, T, N, etc AND the respective personal priority lists are equivalent for the different people. Since this is often impossible, your personal priorities are nothing but ... yours and in any discussion they should be considered for nobody's but ... your specific case only. If an employee Joe or CEO Mark can/likes/wants to work 17 hours a day that doesn't mean it is an argument for why you should work the same number of hours. Joe may simply have a different framework of personal priorities (even with exactly the same stock, salary, etc, ... even though that case may be hard since an identical similarity metric is usually required). If the start-up does not differentiate you from Joe as a separate human being, than you are just a name on a list of paper for this start-up, and obviously you should not want to work there at all.      Finally, you should make it very clear to them that long hours do not equate to higher productivity. You can always stay 2 hours more a day and just keep staring at your monitor during that time ... They gain nothing and you gain nothing. Lose-lose situation.