I am a Web Developer, full-time, but that isn't so much important.
At my current gig, and at previous jobs really, there is this issue of not dividing up work and planning for it far enough ahead of time so that you don't lose the ability to focus.
For example, I've been working on one project for almost 5 months now, and the approach is inappropriate. I'm given free-reign on how to do, but not when, in what order, the length of time committed, where I work etc.
Management, getting to juggle multiple things at one time, likely doesn't see that a decrease in productivity and focus are inevitable(not just in my case) when there is no diversity in work.
How do I explain that throwing raw effort into something is inefficient, and is only reduces project momentum until a wall is hit.