Comment by loup-vaillant | Hacker News Reader

Comment by loup-vaillant | Hacker News Reader

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I recall that some studies showed that long term productivity is maximized at around 40 hours a week (at least on average) [citation needed, please]. When we go from 40 hours to 60, productivity rises temporarily, then falls. The fifth crunch time week is even less productive than a standard 40 hour week. After 2 months, the benefits of the first week are cancelled out. Finally, when we go back to 40 hours a week, productivity plummets, then rises to it's standard level.

But the most interesting thing is that long term perceived productivity is higher at 60 hours a week than at 40. Because of that, it is very difficult to realize that overtime is a mistake (emergencies aside).

I would also understand that not all people are alike. Some may be most productive at 35 hours a week. Some may be most productive at 50. But 60 hours sound like much. Maybe you could try to work even less for a month and see the results? (And of course try to measure your productivity reliably. Going from 60 hours to 50 or 40 may be beneficial, but less so than going from 90 hours to 60.)

Here's a meta-citation for you: http://news.ycombinator.com/item?id=971708

In short, Henry Ford did experiments in his factory and decided that 40h/week was optimal. Unfortunately, this figure has stuck, even though newer research indicates that for knowledge work and creative work, less than 40 is more appropriate. (35-40 suggested by these slides: http://www.lostgarden.com/2008/09/rules-of-productivity-pres... )

I know the same numbers, but they are for programmers. There are jobs where number of hours worked is by far the best predictor of output. OP's work may or may not be among them - sometimes science is a lot more like picking cotton then creative design.

Then they need to change the way they operate their labs, because they don't need someone with 25 years of education picking cotton.

Wow, if one can increase productivity by reducing hours from 90 to 60, then again (as you say) from 60 to 40, then what really is the optimal hours worked per week? I would think it largely depends on the task at hand - manual labor or academic. I know when I framed houses I could do 6x10s and was wasted beyond that and useless, but mental work can be exhausting also. I know with practice one can build up the ability to work longer hours physically and I suspect with training you could do the same mentally. The bigger question, however, is people are expected to have a life outside of work, too. Personally, I'd like to see 35 hours as you suggest as the law.

For the software industry at least Steve McConnell's classic Code Complete cites several studies showing that total productivity (not just per hour productivity) is maximized at just slightly above 40 hours per week, and bouts of prolonged overtime don't generally translate to greater output. My own anecdotal evidence tends to support this.

My personal limits hover at around 30/35 hours a week. Any additional hour is spent surfing the web, struggling the urge to sleep, drinking tea, in brief various task that may easily pass for work but aren't productive at all.

I wonder if a typical trait of successful founders is to be excited/determined enough to do good work (=results/time) while putting in obscene hours. Is this true?

No. Pretend otherwise if you want by saying 'well what if it is this kind of work' but consistently working more than 40 hours per week is counter-productive. Every study shows this.

And there's no need to put in obscene hours, or expect it. As it's counter-productive... See where this is going...

These studies were done during WW2 to investigate ways to increase productivity in the US arms factories. Note that this was with a workforce that wanted to produce as much as possible, not a workforce that was coerced to.

Their conclusion to maximize productivity was to work 40 hours most of the time, with occaisional bursts at 60.

My view is everyone is built and wired a little differently. I love these behavioral management studies too, but certainly there exist people who can stay very productive at the 80 hour a week mark for a few years.

If the professor mentioned properly selects for such people out of his mountain of applicants and the group's culture thrives on it, then he's running a tight ship.

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