This is basically from the German base game. There, the Sentry and Guard commands were named Patrol and Guard (translated back). Naturally, when issueing the Patrol (Sentry) command, I was quite flummoxed why it didn't work as I thought it would.
So, why isn't there a Patrol command? Or at least the possiblity to add multiple waypoints to a ship? It would cut down micromanagement for scouting, for mining, you could have border patrols...