Would you like to go to a doctor who had taken his last medical course in 1948? You have to keep changing and keep learning so that you are constantly challenging yourself, adding a few new songs to your program every chance you get. If you don't, the world will pass you by.
Failures don't plan to fail; they fail to plan.
You do not get what you want. You get what you negotiate.
Unless you work in demolition, don't burn bridges.
You're a lot better off being scared than being bored.
Expect to make some mistakes when you try new and different approaches. Sometimes colossal failures lead to spectacular successes.