When it comes to drafting players, NFL teams can either draft the best available or draft for need. Over the long haul, teams that draft the highest-rated players tend to fare better. Drafting for need often forces organizations to reach for lower-rated players, thus diminishing the value of the pick.
However, if a team has a significant hole at an important position (quarterback, offensive tackle, cornerback), it might be justified in reaching for a lower-rated player.
This is the dilemma the Houston Texans face with the No. 1 pick. The best player on the board is Reggie Bush. Bush is a phenomenal talent and if the Texans want to maximize the value of their pick, Bush is their man.