Criticism, by definition, is an expression of disapproval of someone or something on the basis of perceived faults or mistakes. When faced with disapproval, people step back, put guard and usually decide to ignore it, or defend themselves.
First case (ignoring) appears when people don’t care about someone’s opinion and they haven’t invested much time/effort into what was criticised.
Second case of defending or justifying actions appear when lots of work was put into the object of criticism, or we care about someone enough to let them know they are wrong.
It is crucial to understand that each critique comes from frustration of one person, important to us or not. Think about it… if they were frustrated, and they bothered to let you know what was causing their pain, give yourself time to listen to what they have to say.
Instead of ignoring the critique, try to embrace it. Instead of letting your emotions overwhelm you, try asking more questions to get to the root of the problem. Even if you feel they are wrong! It might lead you to a new realisation and a clearer image.
Ignoring or defending won’t do us any good, as next time, the same person might not be willing to spend their time letting us know what we’re doing wrong.