How fixed is your personality? This is a question that comes up time and time again on development programmes when people are looking at personality profiles, whilst thinking about changing behaviour, yet also being told to be authentic! During today's discussion I hit on an analogy that seemed to work well, which is that you could regard your personality as being like your face.
To a large extent, how you look is genetic, and clear by very early childhood. However, over the years your face will change through age and life experiences. You may pick up scars or other damage. And at any moment, your emotions will change your expression - in some cases to transform your look. And a habitual attitude, which produces a habitual expression, can "set" on your face - like the permanent frown creating wrinkle patterns, or conversely the permanent smile creating lines. But you are always recognisably you.
You can deliberately change your looks (to look your best) by work from the inside out on lifestyle, health, attitude or emotional state. Or you can do surface level work on personal grooming. But whatever you do, you will still be recognisably you. Unless of course you go too far down the cosmetic surgery route! And everyone knows when it has gone too far - because your face is no longer authentically you.