Tony, I like your work and have left comments on more than one occasion.  But....   I quit posting a rating on other people's work long ago.  I haven't allowed ratings on my own postings  for a long time either.

@ ICM 

Does my reluctance to rate someone else's work cause that overall average to fall?  In other words, does a rating box left blank average in with other ratings as a "0"? 

If that is the case,  it doesn't seem fair to the artist that wants high ratings and it doesn't seem fair to a viewer who likes an image and wants to say so to the artist; but feels  forced to vote a rating when that viewer doesn't feel qualified, or inclined to vote a rating. 

If my leaving a rating box left blank counts as a zero, then I imagine there are a lot of artist who would rather I didn't comment even if I liked their work.