Critique is an easy way for people to slander any kind of work you do. Whether it be art, dance, music, acting etc. Some people may try to protect it and say that critiquing is good, but its not. The antonym of critique is constructive critisism ... GET IT RIGHT.
Critique is a dangerous weapon. Its the easiest way to tear into the soul. Possibly making an interesting murder weapon. If you want to kill an artist ask questions like these:
Why did you choose to use only one canvass?
Do you think the use of those colours were effective and why?
Basicly asking questions over and over, rather than commenting on the work itself it the best method. And answer questions with questions.
"I really like how I used the paint here and here. Thats why. Did that answer you question?"
"Did it answer YOUR question is the question?"
"He/She obviously knows nothing about art. This critique is over."