Because software isn't something that you can just buy off the shelf given enough money, otherwise Bill Gates would have been Apple.
It also requires taste and vision, two things that Kanye West utterly lacks.
It also requires taste and vision, two things that Kanye West utterly lacks.
Popularity and quality are orthogonal.
Kanye's music, particularly from before the last few years, has been well reviewed by critics. His shoes were popular among "sneaker heads", or people for whom sneakers are a hobby.