I get too involved in the current project to focus on other projects. Anxiety used to cause a nagging feeling in the back of my head, that I'm forgetting a lot of other things I need to do. Over the years I've used OCD and depression to beat it back.

I watched my dad keep lists and lose lists and forget to read lists, when I was young. He still got the important things done (make lunch for work, fix car, goto bank, etc), because he could keep that in his head, but he had piles of side projects he couldn't work on because they weren't on the latest todo list.