As a child you idolize your father who, to you, is the strongest and smartest man you know. He's always the guy stronger than any monsters under your bed
As a teen you spend so much time pushing against each other and fighting and there's nothing wrong with that as you are just trying to figure out who your are as you grow but unfortunately dad takes the brunt of your whacked out hormones and anger as you try desperately not to be like him and become your own man.
In your 20's there's a bit of a separation from each other but you still love him even though now you're fully convinced you're nothing like him at all although your GF or wife constantly tells you how much you ARE like him.
in your 40's you finally realize that you are EXACTLY like him and again he is the smartest and strongest man you know and realize if you're only 50% of the man he is you're doing okay in life.
Not everyone has this exact experience as relationships are much more complicated than broad generalizations like this but for me I love my father and yes he is the strongest and smartest man I know even though he still hasn't memorized his own WiFi password.