Note: I endorse neither of these foolish statements, but have seen them often about the sites. Anyone who endorses both of them will not be receiving further profile visits from me; it's the only way for me to satisfy both these unreasonable demands at once.
(1) "rate every photo or stash you view."
(2) "rate everything a 10/thumbs-up or don't rate it at all."
Can't really do 1, and definitely will not do both 1 _and_ 2.