John Steinbeck said this quote
“ And as a few strokes on the nose will make a puppy head shy, so a few rebuffs will make a boy shy all over. But whereas a puppy will cringe away or roll on its back, groveling, a little boy may cover his shyness with nonchalance, with bravado, or with secrecy. And once a boy has suffered rejection, he will find rejection even where it does not exist—or, worse, will draw it forth from people simply by expecting it. ”