Do you ever watch something and just think: “That was written just for the fans”?
Scenes that seem as though they were designed to be awesome more than anything else. Dialogue that seems made to be quoted. Moments of tension or comedy that are manufactured to titillate the audience. Sometimes fans of a show or book pick up on these things on their own and take them into their hearts, but sometimes it distinctly feels as though the creators put things in there just to appeal to their audience.
The most obvious of this is the root of the words “fan service”, defined as a random and mostly irrelevant action that plays directly to the audience’s (and chiefly the straight male audience’s) interests: a sudden gust of wind blows a skirt up! An event happens within the show that calls the female cast to dress in scanty or adorably provocative outfits! A sudden rainstorm thunders into existence just above the main characters’ location and everyone happens to be wearing white shirts!
Not to say that this exists solely for the male gaze; depending on the target audience, these instances will occur to males and females both. An important conversation just happens to take place while a toned male lead is working out! There is a bathhouse scene for little reason other than comedy and implicated nakedness! Characters wear second-skin spandex battle suits that may not be historically accurate!
Or, because writers do acknowledge that flashes of attractive people is not the only thing that humans get excited by, they could throw in some really cool mechas and fight scenes and explosions.