In my mind, it's not the amount of time one works, but how efficiently they use that time. We all know someone who puts in long days but gets nothing done because they spend half the time on Facebook or MSN Messenger. We also know other people who are in the lab 5 hours a day and finish their degree early. Most people probably fall between the two extremes.
That discussion made me think about a related topic: how does a supervisor or advisory committee makes the decision that one's project is enough for a PhD? There seems to be quite a difference between what passes for a PhD-level project, even in the same lab. DH's previous lab is great example of this:
His PhD project was to design and build a new type of "bicycle". He started from scratch, learned the theory, designed each part of the bicyle, built each part, put the whole thing together AND made sure it worked.
Another student in the same lab is supposed to design and build a new pedal for the bicycle. That's it. It doesn't even have to work. They both started at the same time, and DH defended his PhD a year ago...the other student is still slogging a long with no end in sight. How do these two projects warrant the same degree?
I understand that, in a lot of cases, it's like comparing apples to oranges: maybe someone has a smaller project but is studying it more in depth, or maybe another has a crap load of data and is just doing simple analysis on all of it. It all depends what the point of the project is, I suppose.
However, in some instances, it seems that some students definitely have a lot more work to do in order to get the same degree in the end. Is this because the advisory committee, or whoever it was to okay the project, wanted that much work, or is it the student who adds the work themselves?
What happened in your PhD? Did you find the amount of work you did was comparable to those around you? Did the amount of work expected for your project change at some point?