A lot of holsters you buy from many companies use thinner Kydex and lack retention adjustment capability. In light of these two things, they need to build the holster in such a way that it will sufficiently and safely grab the firearm, and this is usually achieved through an aggressive retention notch on the trigger.
Where we can, we strictly use .093 Kydex or Boltaron for our holsters to achieve the right amount of durability in our products to ensure a long life for the holster. When using thicker plastics, overly aggressive retention notches can cause overly aggressive retention, which can in turn interfere with both holstering and drawing the weapon cleanly.
The amount of retention we aim to achieve is a proper amount of grab where a direct jolt or force won't move the weapon, while at the same time a quick smooth draw will bring the weapon out without any catching or snapping during the draw.