When you fall in love with someone, you love everything that comes from that person. Likewise, through spiritual knowledge and shadana when you come to know God and fall in love with Him, you like everything that comes from Him. As a true devotee you appreciate everything He has to offer you without altering it a bit. He/she sees God creation as a perfect painting and appreciates it without trying to alter it in anyway. Keeping the hair unshorn is a sign that this person has surrendered to the will of God and loves the way God has chosen to made him/her. Moreover, every time you cut your hair, they grow back. A person with wisdom can see this as a wish of God to not cut their hair. When human lost their hand, leg or any other part of the body, God does not grow it back though He has the power to do that [lizards regrow their lost limbs], but He keep growing you hair even till your last breath. Person with love for God and shadana understands this and comply with how God wants him/her to live and appreciate their hair a precious gift of God. Person with shadana knows that in God's eye hair are far more precious than any other part of my body. Rishis were not lazy or too busy. They loved God and everything He has to offer.
