Extrinsic Self-Esteem is such that is dependent on external conditions like the type of music you listen to, the sport you practice, the films you like. . . As such this kind of self-worth is liable to deterioration and constantly needs to be reaffirmed. Imagine yourself to be a famous football player whose career just got forcefully and ultimately finished by an accident, never able to play football again or to gain money by doing so and affording the lifestyle one has become accustomed to.
Not few would lose motivation for life and would end up seeing nothing but hopelessness for a scary and unpromising future upon experiencing such a loss of identity. Why? That is because almost all the worth of life etc. was measured by this now finished football career and lifestyle. Maybe even your wife was just in for the money and has now left you. Well shit. So much for the dangers and the unsecurity of external self-esteem.
Intrinsic Self-Esteem, on the other hand, is independent of such external conditions. It is rooted in the intrinsic knowledge that one is just fine, that good and bad are just categories measured by specific contexts and nothing more, that everybody is good or bad in some respect and that we all are beings of the same kind, self-conscious and full of potential. There is nothing to lose and nothing to gain for one is already content and wholesome.