As a developer, I don't know why you'd care? Temporary files should be programmatically cleaned up ASAP, at worst during program termination. There are exception to that, like auto-save file type concepts, but even those exceptions leave me wondering why you'd care?

As a user, you'd care, but the answer is the same as with any temporary file: "Files stored in the folder can be removed at any time by system or by user via Disk Cleanup."