In a multi-step workflow, you have the chance to add the next step upon completion of the previous step. I've discovered that if I don't add the next step immediately after marking the previous step complete, I can't add it at a later time.  I CAN add a new blank action or a workflow to that exiting action by using the lightning bolt. But it adds the entire workflow again, including the previous steps that I have already recorded.

My suggestion:

I would love to be able to go back to a workflow in Record Actions and add the next step at any time of my choosing, even if I completed a step but failed to add the next step (whether I made a mistake, or felt I wouldn't need it).