No matter what they say, as a Man, don't show your weaknesses

Why ?? What happens if you show weakness?

I think people will take advantage of that one weakness you've shown in the future. No matter how the situation forced you to expose it, they will definitely use it to defend themselves in the future if something goes wrong. So as the author says it's better to not expose ourselves to others totally. Besides, there's a self. And we need to keep a few things for ourselves!

Yes, never shed a tear in a professional setting no matter what the gender is. It will be used against you. However, being vulnerable is a part of personal relationships, real relationships.