Rating threads? WTF

[Kaiyosama]

Just something I noticed when responding to another thread. I could rate it on a scale of 1 to 5. Which leads me to ask... why? And wouldn't 1 to 5 make a great band name?

 

[Dragongirl]

I am pretty sure it is a built in thing. I could see some use for it in threads in certain forums like art or story hour, but not much else.