The literal meaning: the perception of beauty is subjective.
Subjective: Based on or influenced by personal feelings, tastes, or opinions.
The below comic is titled "Wrong Century" by Tomas Kucerovsky.
The look of wistfulness in her face punches straight through the heart. In a different time, her weight would have been considered traditionally attractive.
"The world is not full of Attractive People and Unattractive People. It’s full of people who are attractive to some and not to others. I hear from trolls all the time who complain that they don’t want to be “forced” to find nasty, ugly fat women attractive – which utterly baffles me, since the last thing I want to do is encourage fat-hating dicks to date fat women. You don’t find fat people attractive? Fabulous. Don’t date them. I will find a way to pick myself up and move on without your love. But to assume your lack of sexual interest in fat chicks must be universal – or that the mere existence of self-confident fat people having healthy relationships somehow “forces” you to find fat attractive – is the height of fucking narcissism."
— Kate Harding
“As long as we live in a culture that tells women that being admired and desired for the way we look is merely the normal condition of womanhood, something fundamental to our sex, it will be considered acceptable to evaluate women for their decorative value. As long as it’s considered acceptable to pass public judgment on women’s bodies, often negatively — to snark on and condemn and make fun of things that are truly beyond an individual’s control — in public, then it’s open season on all of our bodies. As long as women are in competition with one another to have the ‘best’ body, we all lose. As long as there persists a single, narrow beauty ideal we are all instructed to live up to, none of us will live up to it. This game is rigged. There will always be some critic who can tell us where we are found lacking.”
— Jenna Sauers