When was the last time you did something that scared you? instilled this fear of failure or inadequacy? There's a rush of senses when that happens, a rush of adrenaline preparing you for whatever is next. Similarly so, these reactions are the same to when you are experiencing fun.
I believe they exist hand in hand, because more often than not, overcoming a fear is one of the most rewarding things someone can achieve.
Have a think, what terrified you as a kid? a physical activity? public speaking? being the new kid?
All these fears rooted around our sense of self stays with us as adults, and we tend to lock those up, letting it become our own pandora's box.
What if we could use our adulthood to banish those fears away? wouldn't that be amazing? Think of the possibilities that could offer you in your own self development.
Now nothing worth change comes easy, BUT what is the worst that can happen? When facing our fears, it seems like everything is at stake, and that is valid. And when we think about something fun, we get giddy and excited to tackle it. Breaking down that wall, unlocking that box, letting yourself move on and over a road block is far more rewarding. Find the fun as you would when experiencing a fear.
Fear & Fun are two sides of the same coin, and you decide where it lands.