Note: I did not also know that feedbacks also limited, so thanks op for describing about itself.
The limits were probably introduced due to
feedback spamming by some trolls which I think was a good move by the administrator.
I also just found out that a person can only send 5 ratings to the same 1 user profile. But do positive, neutral and negative count as 5? I mean, for example I have sent 2 positive ratings, 2 negative, and 1 neutral for one user. Can I still do the 6th for the same user?
Whether it's positive, negative or neutral, it still counts as a rating. Theymos is quite clear that one can never create more than 5 on a single profile.
What's the point of sending someone a positive, then a negative feedback at once though?