Originally Posted by smokepole
Depends. If it's wet yes. If you're splashing through creeks yes. If you're walking through grass, stubble, gravel, scree etc with trail runners or low top boots and want to keep debris out, yes.

If none of the above and you need to be quiet to stalk up close or it's warm out, no.

I wear gaiters more often than not. In addition to what Smokepole said, I also use them in the desert to keep the cats claw from ripping my trousers to shreds and they make passable snake gaiters.

I'm about to go on a mild-weather recreational backpack up to do some fishing at a timberline lake. Probably won't wear gaiters. I don't expect to do any climbing where I might encounter snow up high.

Wind in my hair, Sun on my face, I gazed at the wide open spaces, And I was at home.