Getting sidetracked, and watching TV for a few hours too long? Or browsing LW/reddit/TVTropes/<your-poison-here>?

Sure poor managment of time could the factor, but it could also be having too much stress in your life. Being in a bad relationship, taking on too much at work, setting unrealistic goals.

Or accidentally having your alarm clock on the wrong setting?

If it is a continual problem, being in too much of a hurry to complete small tasks. There are tons of potential causes. My point was that it might not always be the most productive thing to dismiss them as non-relational.