What Do We Mean by 'Critical'?

Just thought I'd bring up from my comments one by Katy Evans-Bush which seems to me one of the most sensible and indeed important things to have been said in the recent debate about reviews:

The word "critical" doesn't have to mean "negative" - it can also mean "expressing or involving an analysis of the merits and faults of a work of literature, music, or art". I think "I like it" or "I don't like it" can be of some use, but if a reader discusses a book in terms of what the author was trying to achieve - whether the book succeeded in that project, how its various elements operated - it might never be necessary to say "I hated this!"