Cause flannel looks cooler
So this thing does what it says. It dries quick and it's warm. I've also noticed that it's so thick that it pretty much blocks the wind. I use it hiking, biking, and as a base layer (it's long enough that it will hang below most jackets). I've also used it as an outer layer in the spring. Three stars because I wish it had a little bit of stretch, which would make it a LOT more comfortable. Also, it has a boyish cut (straight up and down, which means tight on the chest and hips and loose in the waist for us ladies...).