Why are people more content with living in mediocrity instead of trying for more?

This is in reference to to dating , in any or most areas of life this mentality is pretty much frowned upon but I’ve noticed in dating a common term I hear and even in some other areas of life is “be realistic “

Im so sick of hearing that damn phrase from people when there are so many examples of life and in our history the literally contradict that way of thinking.

Example I’ve been tryna shoot my shot with girl for all intents and purposes she’s out my league a pretty girl with money and a large following online despite a lot of key changes in my relationship with this girl that might point towards potential I’ve continuously been argued with and told it won’t happen and to quote on quote be realistic when I know in my gut there’s something more.

Bet people told that girl who married Justin Bieber the same thing when she was just a fan wanting to marry him, Now she’s his wife.

Or in other areas like science everyone told the inventory’s of the air plane it’d never happen well we all know the ending to that story. Stop down playing people’s dreams because you believe it’s unrealistic based on your small minded world view.

Even in my own life I’ve done things at points and seen things that I thought were impossible but I was proven wrong and I proved myself wrong. Maybe I’m stupid or a fool for thinking the way I do but why to would I want to keep a realistic world view instead of shooting for something more even if I do end up failing I’d rather have know I tried and failed then to have never tried at all.
Why are people more content with living in mediocrity instead of trying for more?
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