Why Defeat The Devil? - Chapter 27
The quest tickets that were categorized, vetted, and published by the guild were not segregated according to the reward but the level of difficulty and danger.
The higher its grade was, the more difficult and dangerous the quest would be. Hence, the rewardwill be commensurate with the difficulty level.
It was not an absolute rule, however. There were highly rewarding quests in the lower grades as well.
Usually, those quests were rather safe whereby the accomplishments were not much of a challenge. Nevertheless, they took a long time to finish. At times, certain prerequisites or even luck was needed to complete the task.