Title pretty much sums it up. In my case, when I dirty and cook a Maya command chain's Command Server End, everything up until my Partition by Attribute TOPs cook. They just stick around with the “Not Started” badge. Is there someplace I can inspect why it might not want to start cooking?

Actually I've noticed in a couple of times not even inside the loop that I have to cook twice to get Partition by attribute to start. Is this normal?

Found the issue: I had a python script running in before the partition. Its “Evaluate Script During” parameter needed to be set to “Generate” instead of “Cook (In Process)”