Silence is psychologically harder than combat. The perimeter officer has to manage trigger discipline when a cat knocks over a trash can. He has to identify the suspect running out the back versus a neighbor walking their dog. He has to radio in "Sector clear" every 90 seconds without the adrenaline of the breach.

The ten are not just there to catch the bad guy. The ten are there to rescue the six.

The ten exist to make the "flight" option a mathematical impossibility. A perimeter with only six people has gaps. A perimeter with ten has overlaps. But a perimeter with fourteen is overcrowded, leading to fratricide (friendly fire) via sound confusion. The 6:10 model is a direct response to the failures of the 1990s and early 2000s "Blitzkrieg" style of SWAT. Back then, teams ran 10-man entries. The logic was: "More guns in the room wins the fight." But statistics from the National Tactical Officers Association (NTOA) show that in structures smaller than 2,000 square feet, any entry team over 7 men creates a "Fatal Funnel" inside the fatal funnel.