There are 3 reasons to train MA: There are for - health, - fun, - combat. Why do you still want to train hard when you are 80 years old? For health? You don't need MA. For fun? There are others thing that may give you more fun. The only reason left is for "combat". What's the usage for your "combat" ability when you are 80 years old? You try very hard not to let a 20 years old to beat you up when you are 80. Is that ego? Of course it is. Is it bad? I don't think so. If you can utilize your ego to give you the motiviation that you need for your MA traing, you have just converted ego to something positive.