With all jobs I ever had, I always had the same issue:

Being bored and nothing to do.

I work in software, and it usually goes like this:
- Get a task
- Do task
- Submit for review
- Wait several hours, or even days, for review

Usually I spent the "down time" by reading manuals,
working on personal projects (over SSH),
improving this gopherhole, etc.

Other things include playing games (but that feels like
a waste of time), sorting ebooks (instead of reading one),
drinking too much coffee, etc.

But sitting in front of the PC just because you have to
is tiresome. I would rather spent some of this time
outside and work on the problems on my own schedule,
e.g. in the evening or during the weekend.

However, it seems that this is just the way companies
are built. It’s annoying, actually.