[bikamonki]

I think your first point is the most relevant: endless hours stuck trying to finish a project while struggling with a tight deadline/budget. It all boils down to a common problem amongst developers: guesstimates.

I believe it is a shared fault between clients and consultants. The former does not want to spend money/time preparing complete in-depth requirements/functional descriptions, they want to start yesterday and deliver tomorrow. On the other side, the programmer that bids on the safe side (b/c requirements are a blurry incomplete list of wanna-haves and it's better to over-estimate) runs the risk of not getting the contract, so he commits to a dead-end project: underpaid and overworked.

After many weeks of coding stuff that was not on a list, naturally one burns out. One subtlety: the burnout may not be due to the actual number of hours worked but to the fact that one does not see an end to it, one can never call it done (pressumably waiting to collect a payment due on delivery).