Ask HN: If clean simple design is better, why are magazines so busy?

I happen to think that clean, flat design is the bee's knees. But in critically evaluating my own assumptions, I don't have a good answer for why the magazine industry, which has a much longer history of graphic layout than do apps and websites, does not seem to have ever gone that way.

Even leaving out covers, which have to vie for magazine rack attention with each other, the inside pages of most magazines are a mess of color and gradients and designs. Thoughts?