This started as a Google+ post about an article on getting top engineering talent and got way too long, so I'm posting here instead.
I wholeheartedly agree that 18-hour days are just not sustainable. It might work for a brand-new startup cranking out an initial release, understaffed and desperate to be first to market. But, at that stage, you can expect the kind of passion and dedication from a small team to put in those hours and give up their lives to build something new.
Once you've built it, though, the hours become an issue, and the playpen becomes a nuisance. You can't expect people to work 18-hour days forever, or even 12-hour days. People far smarter than I have posited that the most productive time an intellectual worker can put in on a regular basis is 4 to 6 hours per day; after that, productivity and effectiveness plummet, and it only gets worse the longer it goes on.
Foosball isn't a magical sigil protecting engineers from burn-out. Paintball with your coworkers isn't a substitute for drinks with your friends or a night in with your family. An in-house chef sounds great on paper, until you realize that the only reason they'd need to provide breakfast and dinner is if you're expected to be there basically every waking moment of your day.
Burn-out isn't the only concern, either. Engineering is both an art and a science, and like any art, it requires inspiration. Inspiration, in turn, requires experience. The same experience, day-in, day-out - interacting with the same people, in the same place, doing the same things - leaves one's mind stale, devoid of inspiration. Developers get tunnel-vision, and stop bringing new ideas to the table, because they have no source for them. Thinking outside the box isn't possible if you haven't been outside the box in months.
Give your people free coffee. Give them lunch. Give them great benefits. Pay them well. Treat them with dignity and respect. Let them go home and have lives. Let them get the most out of their day, both at work and at home. You'll keep people longer, and those people will be more productive while they're there. And you'll attract more mature engineers, who are more likely to stick around rather than hopping to the next hip startup as soon as the mood strikes them.
There's a certain pride in being up until sunrise cranking out code. There's a certain macho attitude, a one-upmanship, a competition to see who worked the longest and got the least sleep and still came back the next morning. I worked from 8am until 4am yesterday, and I'm here, see how tough I am? It's the geek's equivalent to fitness nuts talking about their morning 10-mile run. The human ego balloons when given the opportunity to endure self-inflicted tortures.
But I'm inclined to prefer an engineer who takes pride in the output, not the struggle to achieve it. I want someone who is stoked that they achieved so much progress, and still left the office at four in the afternoon. Are they slackers, compared to the guy who stayed another twelve hours, glued to his desk? Not if the output is there. It's the product that matters, and if the product is good, and gets done in time, then I'd rather have the engineer that can get it done without killing themselves in the process.
"I did this really cool thing! I had to work late into the night, but caffeine is all I need to keep me going. I kept having to put in hacks and work-arounds, but the important thing is that it's done and it works. I'm a coding GOD!" Your typical young, proud engineer. They're proud of the battle, not the victory; they're proud of how difficult it was.
"I did this really cool thing! Because I had set myself up well with past code, it was a breeze. I was amazed how little time it took. I'm a coding GOD!" That's my kind of developer. That's pride I can agree with. They're proud because of how easy it was.
This might sound like an unfair comparison at first, but think about it. When you're on a 20-hour coding bender, you aren't writing your best code. You're frantically trying to write working code, because you're trying to get it done as fast as you can. Every cut corner, every hack, every workaround makes the next task take that much longer. Long hours breed technical debt, and technical debt slows development, and slow development demands longer hours. It's a vicious cycle that can be extremely difficult to escape, especially once it's been institutionalized and turned into a badge of honor.