I've never updated my skill set on LinkedIn. Don't see any value to it. And yet some of my friends who have no idea what I'm working on endorsed me for random p

I've never updated my skill set on LinkedIn. Don't see any value to it. And yet some of my friends who have no idea what I'm working on endorsed me for random programming skill set. There should be a credibility factor when someone endorses you. Say the person endorsing you for skill set x should have been endorsed for that skill set x at least n times before being judged credible. Right now, it's just a "you scratch my back, I'll scratch yours" function.