spam and offensive flags get different behaviours that clear away those things quickest
Spam is often actively harmful (outright scams) - we want our visitors to never click a link that scams them out of money or catches them in spear fishing - thus spam flags clear away those risks as quick as possible
and offensive, well a visitor who shows up and finds visually vulgar images for instance - will never come back here again. So again, those get cleared off quicker than other flags (is my understanding anyway - spam and offensive flags are specially treated by the system)
The Whiteboard
The Whiteboard