Well, I can't say it factually, true, but factually his biggest hits have been his own compositions. Which would speak to a general overall appeal his own songs have versus others. Not that that speaks to artistic credibility. But I think his most melodic, most complex, most percussively and vocally well arranged songs, and most rhythmic have always been his own. There's a brilliance in Michael's own songs that it lacking in other song's either written by others or co-written. Like if you listen to "Smooth Criminal", for example, it's scary how he's able to take what on the surface seems to be disjointed cords, or stacatto cords, and make them flow so well, etc... One other thing is how atmospheric and vivid his own songs are. They set a mood that other songs just don't, like "Who Is It", "Billie Jean", "Will You Be There", "Childhood", "Little Susie", etc... His own songs are just rich visually and emotively.