I think it comes down to how a given user works and thinks. Personally, I agree with you about hierarchy (my app doesn't have it and the issue comes up periodic

I think it comes down to how a given user works and thinks. Personally, I agree with you about hierarchy (my app doesn't have it and the issue comes up periodically) but I know some that need it. I'm often amazed at how such a simple problem (managing tasks) is solved in such different ways, each which suits one subset of the population! Sometimes the tool is irrelevant. I have one friend who used a directory structure and text editor (pretty simple) to create an enormous cluster of tasks he'd never get to. Many thousands, like the Windows registry after a couple years of random software installs. His issue was just needing a mechanism to periodically clean it out, so a change in approach rather than a different tool.