"For nothing will be impossible with God."
I think one of the major reasons people don't know their call in life, is that they overlook it--not realizing its importance. Your call may not seem significant in the beginning because it's just a seed, but it has potential to turn into something great. It needs you, however, to tend to it and nurture it. It needs you to see the potential in it way before anyone else does, and then to stay committed to its growth.