Because people will say whatever they want and WOT takes no action to prevent slander and lies, teh ratings of any site are suspect. Sure the really bad sites are figured out, but also legimate sites can get a bad rap just because people are ignorant about what the site provides. Phishing, spam, fraud are strong words and should be used only when you are sure.
This site is the second thing that I rely too to see the trustworthiness of a site, first is common sense.
First site that I have seen that has many ratings but has perfect green rating lol but yeah this site is generally safe.