There’s times where I’m trying to have the flowchart resemble the requirements doc. This can result in using NOT in the condition so that I don’t have too many lines crossing over each other. I also have times I want to have multiple FD point the false node to the same error handling/notification routine so I’m not duplicating code. The best reasoning is so that the flow matches the requirements and I can minimize the conditions that have NOT in them. It’s sometimes easier to test for a negative.