Because that's what The Situation was hoping for and because he wanted the pipe dream the Cards must have wanted the Texans assets.
mortreport Chris Mortensen Falcons gave up 27th, 59th and 124th this year & 1st and 4th round picks next year
It's likely a guarantee that the Texans will draft somebody so uninteresting that they will cut to a commercial and not show any highlights of him.
So we're going to end up with Prince? The Purple Rain references will get really annoying after a while.