I hope I don't sound too much like Bill Clinton when I say, it depends on what your definition of right is.
If right means truth, then it's always the most important quality (as it's rare and beautiful)... but, anything true "always already" (Jacques Derrida) contains kindness. What could be more kind than knowing the truth?
But it's a good question, because it's not as simple as I'm making it sound. What about the Greek tragedy, Oedipus? A king found out he committed incest. What about learning that a lost loved one was found, dead? What about figuring out a relationship -- with someone you long for -- will never be?
Resolution is unveiled, which leads to redemption (or repentance, prayer, and/or good deeds), ultimately cultivating reinvention. In short, kindness comes after truth if we let it—if we have faith in a hopeful belief. We must be optimists for it to work.
I feel that truth allows for genuine kindness. Sometimes, we've got to criticize a friend (which may not seem kind at the time) to help improve on their weaknesses, while encouraging their strengths. Eventually, you act out more kindness by speaking the truth.
Thanks for asking,