Midrash Rabbah teaches that Korach was led astray because he had seen prophetically the distinguished descendants that would come from him, including the prophet Shmuel. R’ Nosson Sternhartz z”l (1780-1845; foremost student of R’ Nachman of Breslov z”l) explains: It is fitting that a tzaddik who reveals Hashem’s da’at (literally, “knowledge”) to the world should be honored, just as the da’at he disseminates is worthy of honor. Moreover, if a tzaddik is honored, his words will be listened to. However, such a tzaddik must be exceedingly humble, like Moshe Rabbeinu, so that he flees from honor and, when he receives honor, he accepts it solely for the sake of honoring Hashem. Korach lacked that humility. Also, he mistakenly thought that Torah leadership is hereditary. If his descendant Shmuel would be honored as a custodian of Hashem’s da’at, then, Korach reasoned, he too must receive such honor. And, Korach thought, he must already possess true da’at. In reality, however, Torah leadership is not hereditary. Rather, it awaits whomever comes to claim it through his toil in Torah, accompanied by humility. (Likutei Halachot: O.C. Hil. Netilat Yadayim 6:67)
