Emissary quests had the highest chance to reward legendaries so people felt compelled to farm them even though the world quest reward itself was garbage. I know that once I got my legendaries and saw that I hadn't gotten a single mount from exalted+ I gave up on doing world quests for a long time. "What's the point of getting 10k rep for a 1% chance at a mount?" Others kept farming regardless of the low chance at the mount though and it kept them going. In BFA there aren't legendaries or RNG mount rewards from emissary chests (that I know of). Although most people hated how RNG legendaries were, it did keep us on a treadmill longer. Is there a similar system to keep us doing world quests in BFA for better or worse?