Because it's a stupid feature, that's why.
All people should be able to assign a thumbs-up (or thumnbs down) to any message. That's really the only way value concensus can be achieved.
See
http://www.useit.com/alertbox/990905.html, an article that's two and a half years old but never truer. The UT just doesn't get it; it never did.
**--** Steve
>>
>>If you are the owner of the thread, you are able to mark a message, from others, as solution or help.
>
>But, what about in cases like that ? That I am just trying to give informations for the UT/Database (on how the thread has been solved)..
>
>Claudio