I have come to the conclusion that a Phd is 60% waiting around for somebody to email you back, or trying to get an experimental setup to work, or trying to get your computer to recognise your USB stick, or just your mouse, if your computer turns on at all, or wondering why the software license has expired, or spending months on a programming protocol because there is a / or a . in the wrong place, or waiting for people to come back from holiday (lucky them), or repeating something because the lab tech contaminated your sample, or finding that somebody has 'borrowed' your chemicals/equipment/lab bench/desk/girlfriend and waiting for them to return it.
Yep, its a bit frustrating.