Why do I need to check for authority again

First off, sorry for the long question, but I am a complete beginner to networking, so this might be a dumb question.

I am trying to make a multiplayer shooter using a listen server. The reason I am using a listen server is because you have to host a server to use a dedicated server, and you have to build Unreal Engine from source to use a dedicated server.

I figured out how to register the bullet impact on by character class, but I was wondering why I needed to check to see if the player is an authority more than once?

I switch based on authority, but then I have to check the local role again. I was wondering why I needed to do this because if I only check the local role, or only use Switch Has Authority, it doesn’t work.

Would this be a problem if I were to use a dedicated server? I think that a listen server would work better for my project, which is why I’m hesitant, but if there is a problem with having a player on the server, then I might want to use a dedicated server.

After setting up a simple health bar for each player, I noticed that the server player’s health bar wasn’t updating, but the client’s was. I also learned that you have to use C++ to use a dedicated server, so I don’t think that is an option unless it is necessary.

Sorry for al the replies, but I was wondering if you would need to use C++ or compile from source to use a dedicated server model in UE5?