short answer, it depends. fenders don't work miracles but certainly are helpful as well as a pain in the butt to set up

when playing in the dirt, be prepared to get a little dirty & maybe wet

this was after a ride in the pouring rain. decided to get fenders but then avoided riding in pouring rain



some favorite photos of my fenders

sticks can get thrown into your spokes & derailer

side spray can get your feet wet even if you have fenders



this photo is not mine

if you do fender-up, will you add mudflaps?

you think you'll avoid water, but it's all good, until it isn't