Aldon Smith is the best-case example of a rookie not starting while making an impact. Playing mainly on passing downs, Smith finished 2011 with 14 sacks, half a sack behind Jevon Kearse's 1999 record of 14.5. He also ended the season behind only Von Miller in NFL Defensive Rookie of the Year voting.
Players taken early in the draft are expected to contribute immediately. Note how Cam Newton and Von Miller were the first two picks of the 2011 draft and won the Offensive and Defensive Rookie of the Year awards. Not all players can instantly contribute to their teams.
It's not always for the worst when a player doesn't start right away. 2003 No. 1 overall pick Carson Palmer didn't get on the field for a regular season as a rookie. Palmer made the Pro Bowl in his second year as a starter.
Some players won't make the starting roster in 2012 due to competition and others aren't ready for prime time yet. The following is a list of those projected players taken in the first two rounds of this year's NFL draft.