Everyone puts the pants one leg at a time – Jean Claude Killy

I wasn’t able to find an exact reference to this quote, however i found a similar idiom :
He puts his pants on one leg at a time
(one) puts (one’s) pants on one leg at a time

This quote was supposedly said by Jean Claude Killy, a French former World Cup alpine ski racer. He dominated the sport in the late 1960s, and was a triple Olympic champion, winning the three alpine events at the 1968 Winter Olympics, becoming the most successful athlete there. 

The 2 quotes are similar, with a slight difference in the subtle meaning.

He puts his pants on one leg at a time

This idiom is often expressed to mean that the person is only human, in a way do not put him on a pedestal and treat him like a god. Used especially in reference to someone who is of an elevated social status, such as a celebrity, business tycoon, star athlete, member of royalty, etc.

Everyone puts the pants one leg at a time

– Jean Claude Killy

This quote means that we are all human, we all make mistakes. We all have vulnerabilities, and fears. This quote can be very helpful to calm stress when having to talk with a person of more elevated social status.

My opinion about this quote:
True that we are all human and make mistakes, but we are definitely not all the same breed.
On one side you have 99.9% of humanity, on the other, you have people like Elon Musk.