I personally think it's the inability to to what you used to be able to do. Because once I get rolling I can keep it up for a decent amount of time but the energy required to get the inertia is just way too high in the morning. My batteries are lowest in the morning and my thoughts are worst in the evening but not being able to do stuff during the day really just takes the cake in what I hate about depression. I don't even care that I'm pretty much a robot with the amount of emotions I'm missing. Just give me my productivity back please