Lack of 'Commitment' is 1 factor why people fail. However, that itself won't give enough detail...There are more to that. Indeed, commitment is the longest n even sometimes tedious goal to mankind. Their reason behind their failure can be those little crap stuff like politics, faith, discipline, communication n so on. No doubt there is always a crisis of commitment at some point in our society.

Which bring me to another point, Where the hell that commitment come from then? The society or within itself? People seem unwilling or reluctant to make commitments, or rather did made one, only to end up throwin everything away. However, there are those driven people that sincerely want to fulfill their commitments. People don't get married to get divorced( Though divorce cases are shootin up like volcano eruption these days), and people don't fail to keep resolutions because they want to fail.

Could 'purpose' be the main reason for the crisis of commitment in life? A great purposelessness has desended upon modern civilization. People at large have lost any sense of the meaning and purpose of life; and without an understanding of our own purpose, there can be no true commitment. Whether that commitment is to marriage, love, work, study, or be a dancer(whatever that suits you). Even simple resolutions of our lives will be impossible to achieve without clear and practical understandin of your purpose. Commitment and purpose go hand in hand. For simple reason: we are committed in things we do because it serve us a purpose to live for in life.