An ability to ask other people for help.
This was the hardest one to develop for me. I would rather die than come off as weak in front of others, all due to my tremendous pride. It would convince me that I have all the things needed – my legs, arms, and functioning head. But life is a great teacher. A couple of situations in which you will simply have no choice but to seek help will just be enough. Yes, you do have everything that you need, but one of the crucial points in this list is the people around you.