David K Purdy/Getty Images
If the NFL draft was full of sure things, teams would never screw up picks in the opening round. The reality, though, it that no draft prospect—no matter how safe he appears to be—is actually a sure thing.
Those players taken at the top of Round 1 are typically safe picks, at least, though there are obvious exceptions—guys like Dion Jordan and Justin Gilbert are usually anomalies of the early first round. Once you get to the middle of the opening round, however, you tend to find more prospects who come across as risks.