During the 2011 season, the three teams with the best offenses (New England, Green Bay and New Orleans) also had the worst defenses, which explains why none of those teams were happy to run out the clock, instead always pressuring for points. The current salary cap rules mean that it is nearly impossible for a team to have an excellent offense and defense over any period of time, particularly as cheaper players who play very well one year will likely cost more in the next year. Such tactics are generally referred to as 'Keeping their foot on the gas', and is generally not frowned upon in the NFL.