I thought Paul Buchheit had a seminal insight about this last fall: <a href="https:&#x2F;&#x2F;twitter.com&#x2F;sama&#x2F;status&#x2F;652242405966483456" rel="nofollow">https:&#x2F;&#x2F;twitter.com&#x2F;sama&#x2F;status&#x2F;652242405966483456</a>.