Knowing yourself is something I've picked up from Gary Vee or some may call him Gary Vaynerchuk. "It is rarely spoke of in the business world, because things are sometimes "1st place or nothing" and theres a subconscious standard for everyone." - Gary Vee
I found Gary Vee on twitter, my senior year. He had an article through some magazine website where he spoke of himself and how he knows himself so well and how knowing yourself is a vital knowledge, that everyone should have, to know yourself is to be comfortable and a type of safety mechanism so you do not bullshit yourself in your strength and weaknesses leading to a hazardous effect on your decisions, when you begin to analyze yourself as a person and move forward with growth and progress in your current efforts.
Gary's a very charismatic person and it projects him in interviews and projects while also projecting him into bigger and better things.
In my opinion, knowing your strengths and weaknesses and accepting of all your own flaws is so important, also your level of awareness to your strengths and weaknesses is important too. How can you apply your best efforts if you don't know them. It would be like asking you "what are your passionate about, and not passionate about," like honestly, what do you really know about yourself?
This is vital and this is something I had a strong difficulty understanding myself in life, but constant and consistent effort worked itself out and I'm still working