Julian Barnes said this quote
“ Does character develop over time? In novels, of course it does:otherwise there wouldn't be much of a story. But in life? I sometimes wonder. Our attitudes and opinions change we develop new habits and eccentricities; but that's something different, more like decoration. Perhaps character resembles intelligence, except that the character peaks a little later;between twenty and thirty, say. And after that we're just stuck with what we've got. We're on our own. If so, that would explain a lot of lives, wouldn't it? And also if this isn't too grand a word--our tragedy. ”