I am very disturbed at how I encounter people, particularly young people, who work ridiculously long hours. Furthermore, it worries me that some are deluded about what they might achieve by doing this. Due to a variety of cultural pressures I think Ph.D. students from the Majority World are particularly prone to this.
First let's not debate exactly how many hours is too many or exceptions to the generalisations below. At the end I will give some caveats.
Here are some reasons why very long hours are not a good idea.
Something may snap.
And, when it does it will be very costly.
It may be your mental or physical health, or your spouse, or your children, ...
Don't think it won't happen. It does.
Long hours may be making you quite inefficient and unproductive.
You become tired and can't think as clearly and so make more mistakes, have less ideas, and find it harder to prioritise.
It is a myth that long hours is mostly what you need to do to survive or prosper in science.
I claim dumb luck is the biggest determining factor in getting a faculty position. Furthermore, when I look at people [students, postdocs, facutly] I don't observe a lot of correlation between real productivity and the hours they work.
There are other things that are much more important than long hours. Some of these I have covered in posts about basic but important skills. Others include knowing the big picture, giving good talks, ...
These are necessary but not sufficient conditions for survival.
Yet many who are "lab slaves" seem oblivious to do this. They may have unrealistic expectations about what the long hours will lead to. Some even think long hours are a sufficient condition for survival.
You may be wasting a lot of time.
Because you can't think clearly and/or just do whatever your boss or manager tells you to, you may spend a lot of time on tasks that have almost no chance of succeeding: poorly formulated experiments or calculations, applying for grants or jobs out of your league, submitting papers to luxury journals, ...
There are also all those papers that you or your boss did not finish. You worked long hours in the lab to get the data and then the paper was never brought to completion because you and/or your boss had moved on to the next crisis/opportunity/hot topic.
It may rob you of your joy of doing science.
It may be an addiction.
Workaholism is as dangerous and as costly as alcoholism, drug and sexual addictions. The only difference is that workaholism is often seen as a virtue.
You DO have a choice.
One of the great lies of life in the affluent modern West is that people do not have many choices. This is exactly what employers and governments want us to believe. A problem is that people make choices [e.g. I have to get a permanent job in a research university, I have to have a big house, I have to send my kids to a private school, ...] that then severely constrain other choices.
You may be being exploited.
Universities and many PI's love cheap and compliant labour, whether it is grad students, "adjunct faculty" [teaching staff on short term contracts], or "visiting scholars" from the Majority World.
A few years from now you may regret it.
You may have left academia and realise you could have got your current job without working 3 extra hours a day. Why did you do it? Your spouse [if they are still around] sure wishes you hadn't.
How many hours is too many?
I don't know.
There is significant variability in people's stamina and makeup.
There are also differences in personal circumstances [e.g. a single person versus someone with two young children at home].
Different tasks in science [analytical calculations, writing, discussing, device fabrication, computer coding, babysitting experiments, ...] differ significantly in how taxing they are intellectually, physically, or emotionally. Also, there may be certain deadlines or tasks that require long hours for a short period of time [a visit to a synchrotron, monitoring a chemical reaction that takes 18 hours, the last week of finishing a thesis, ...] .
This is not what I am talking about.
I am talking about an unhealthy lifestyle that does not deliver what it claims to.
How do you get out of this?
First take a break so you can see more clearly the problem.
Set some boundaries. Just say NO!
Talk to others about the issue.
Aim to work smarter not longer.
I welcome comments.