One reason is they answered the immediate questions by signing back many of their own free agents and adding three others: TE Martellus Bennett, OT Sean Lockhart and DB Antwaun Molden. They also traded for veteran LB help in Keith Rivers. These players will provide much needed depth to the Giants' rank and file.
Another reason, is they managed the cap well. By signing several key players at - or close to - the veteran minimum, they are in a good position going into the draft. They have 65 players under contract with an approximate cap figure of $123 million.
More needs to be done with 15 more players coming through the door in the next few weeks, but they will be in decent shape come September it appears.