You need three things to rebuild quickly.
1. A losing record where you get the high draft picks in each round, probably for two seasons.
2. Change in coaching. The coaches didn't get it done, need new coaches plus exit of non performing players.
3. Money. Can't be strapped with a big cap and keep what talent you did have. Can't fill in holes with good free agents. KC and the vikes find talent in the free agent market to keep team competitive.