It's a well known fact that the Rams were loaded with draft picks from the RG-III trade in 2012. The team used those picks to build a team that was young, talented, and most of all cheap - thanks to the new rookie wage scale. They then used that financial flexibility to take a few major swings in Free Agency.
While the first part of that strategy allowed the Rams to build one of the most promising rosters in the NFL, the latter part blew up in the team's face. While they have had some success with the smaller contracts, their big swings haven't worked out.