You don't know what you don't know.
The problem is that many people are to busy or are plum tuckered out to learn new material. And while complete omniscience is not possible for us humans, knowledge is a blessing. The pursuit of knowledge is a noble one, and it can enrich our lives in many ways.
Choosing to live a life of lifelong learning can expand your understanding of everything you do in life. This has so many benefits. Learning about the world around you can:
Help you make better choices
Allow you to see the beauty in even mundane things
Appreciate what you have, and the people around you
Inspire you to make positive changes in your life
Encourage you to try new things
Help you be a more thoughtful and empathetic communicator
Propel you to make more informed choices
And so much more!
While you can't know everything, you can seek to learn and gain knowledge about the things that you do and use in your daily life.
One way to do this effectively is to surround yourself with "mentors." These are people who can teach you about their trade, craft, or business. Just by being around "mentors," you'll gain all kinds of valuable knowledge and insights, and be able to reap the benefits. In fact, your mentors don't even have to be people you know. You can find mentors in what you watch, read, and listen to, as well.
Choose wisely.