a. Begins with man's need for eternal security. Thus the appeal is self-centered, and remains so throughout. Never gets beyond egocentricity.
b. Very similar. Appeal is usually to our natural selfishness. Seems difficult for us to conceive any other appeal being effective than the egocentric one. Begins with the sinner's need.
c. Begins with the revelation of the love of God at the cross (1 Cor. 2:l5). Appeal is to a higher motivation--love and gratitude. Thus not egocentric.