I second this. Trying to be the best at X will have serious diminishing returns. A lot of people stress out because they've put all their energy into one thing and yet they aren't the best at that one thing. Diversification is an easy way to add uniqueness to your skillset (and more importantly, enrich your life/gain perspective).

It helps to get used to being terrible at something at first. Every few years I pick up a different sport and there is that period where I am the worst person in the gym/on the team, etc. With practice, you simply get good at being bad at something, if that makes any sense.