I'm hoping this will be the scenario if you DON"T actively accompany them. Add a random chance you could lose part or the entire caravan before it gets to its destination while caravans are en route. Which would earn your settlement a decent income with traded goods from other places. But if you do say, accompany one, it's a 98% chance the caravan will be sacked by raiders, tribals, Enclave or a Deathclaw or two.

Ugh, making sure your caravans have proper protection sounds an awful lot like an escort mission. The horror! The horror!

Not if all it means is setting it up with caravan guards and equipping them with heavy duty weapons and armor

Lol I'm reminded of all the dead caravans down the road just past Wolfhorn Ranch. Those guys *did not* have proper protection. They have never made it to Novac in any of my games unless I helped them (which I was not keen on doing since I didn't want to piss off the Legion right off the bat).