Learning how to take constructive criticism it often not an easy thing to do. It is a look at ourselves that we do often take the time to do. When we ignore such criticism, we are telling others that we really don't care what THEY think. The term "I'll take that under advisement" isn't just a pat answer to give someone we disagree with. To take something under advisement is to examine what's been said and determine it there is, in fact, merit to what's been said.
Matthew Henry tells us:
"Faithful, friendly reproofs help spiritual life, and lead to eternal life. Sinners undervalue their own souls, therefore they prefer the body before the soul, and wrong the soul to please the body."Put your soul above your body, above your mortal pride and above the desire to reject advice (provided the advice is sound). Be willing to see your own failings and to grow in love and service to God.