What Do You Write About As An Artist?

Listening to great artists like Celine Dion, the Queen of blues or the likes of Tupac and Biggie Smalls (of blessed memories) the greatest that Rap has ever been blessed with. Or the great minds like KRS1 etc. Listening to their music is always on another level because it passes messages of struggle, trouble, pains and success. 
Being an artist is a whole lot more than just having good Beats, good producer who does the mastering and mixing work. 

Recently, in an interview Dr Dre said Hip Hop is more of quantity this days and no more quality. 

Hence, the reason why artists release a song and then it stops making ways after a month or highest six months. 

As an artist who wants to be remembered, you have to write something good and say something good that will be remembered even long after you're gone. 

So what do you write about as an artist?