Substance
There's nothing wrong with being average, yet average people often put great effort into trying to convince the world they're exceptional. Designer clothes, makeup, cosmetic surgery, and even premium automobiles are a few of the surface treatments people display. And while it's certainly good to take some pride in one's appearance, if one's habits are no better than average, then the outcomes one gets will be average.
A facade, or an embellished outward display, is not substance. Substance comes from habits that produce authentic outcomes in your life. Painting stripes on a house cat won't make it behave like a tiger. And you can't authentically demonstrate substance that you have not invested time, money, and effort into acquiring. Mediocrity will reveal itself as the truth, which is apparent from your habits and the outcomes thereof.
If you experience feelings of mediocrity, understand that a lot of other people do as well. Also understand that if you're habitually spending hours of your day consuming social media, TV, or video games, or getting high and drunk, then you cannot and will not be anything other than average.
It's easy to overcome mediocrity. Perhaps what's hard is your head! If you know good and well what your poor habits are, then confront them.
Your allocation of time matters when it comes to becoming your best self. You can choose to stop binging on distractions and start binging on books, exercise, and courses. Take up constructive activities that build your mind and body. Pursue new experiences. Upgrade your habits and you'll upgrade your substance.
Sayonara until next time.