I genuinely think he's bipolar.
I love him. He's so talented. But he has serious mood swings. Bipolar people are also
exceptionally creative. They have depressive episodes and what are called hypomanic episodes, where they feel really creative and come up with so many ideas - and really quickly too.
Stephen Fry is bipolar, and he said he wouldn't change it for anything in the world, because even though his depressive blocks are unbearable, and he becomes almost suicidal during them, he says it's worth it for those bursts of creativity and ideas he gets during his manic periods.
I think Kanye West is either undiagnosed as bipolar, or he knows and is choosing to not go public with it.