Fabric and pocket designs are what it’s all about
Since there are so many types of tools and gear an individual can need these days, having clothing that get hold it is important, there is such a thing as zip off shirts and pants but the zipper locations tend to become uncomfortable especially in extreme temperatures. Everyone has a different type of cell phone and cell phones are quickly replacing radios in many circumstances. Having a pocket that is too large and allows too much movement of an object means that that item will most likely find a way to fall out. Some tactical clothing if designed right, gives an operator wide range of movement and still securely stows and retains gear.
Just about every type of tactical pant out there has a picture somewhere that shows somebody putting a 20rd or 30rd magazine in a pocket. Well from my experience tactical pants are rarely used for carrying rifle magazines, but some are specifically designed for this. The best pant for storing M4 Carbine magazines is the Woolrich Elite lightweight tactical pant, but I will have to say that I wish the pant had a gussetted stitching. While the pants are designed well, they do have a reputation for tear in some situations.