There are exceptions to every generality, of course, but most dogs seem to be such eager-to-please suckups that I lose all respect for them. Classic 'clingy', high maintenance downer.
As a friend of mine says, "Cats and women will always do whatever they damnwell please - dogs and men might as well get used to it".
I'll take the tolerant indifference of the average cat over the slobbering servility of the average dog any day.