Costume designers have a phrase for the first time actors see themselves in their comic book movie costumes. It’s known as their “superhero moment.” Professional actors who might otherwise see a film as just another job are taken back to being a kid playing dress up.
Jason Momoa’s superhero moment went a little differently. There was no mirror in the room so it was his director, James Wan, who turned into a kid again the first time Momoa put on his classic costume for Aquaman.
This is the EXACT same story every actor tells when they wear their “Costume for the First Time.”
Seriously, this is like some mandated thing by the marketing department. Because NO director sees and tests several costumes tweaking each one before filming.