a songs worth?

another day in school and it just occured to me in my boredom, what does it take for a song to be great? looking at some of the most popular musicians today have lyrics that convey depression,pain and anger whether it be anger towards self or anger towards others. just seeing these lyrics it could be said that what makes lyrics great are the negative things they express.but then your riding down the road and your friend puts in a metal c.d the music is heavy and the lyrics arent even understandable but its awesome.its sounds almost hateful also yet when you read the lyrics there about love, kindness and downright good things. this directly contradicts the earlier statement. so now that we see this what is it that makes a song great. well here i believe is the key 1.emotions are great. when you here a song you can understand and its emotional it moves you.2 when you here a song thats just screaming and unable to understand you like it because its full of energy. 3 but then even songs that have no lyrics are enjoyable because its a feeling you can feel the passion being displayed by the writer/composer. so if you put all this together THATS what makes music great. a song full of passion, energy and lyrics that move your heart to action.these are the kind of songs i want to write. sorry for rambling but i just thought id share this with everyone else.