וַעֲצַת ה' הִיא תָקּום (Mishlei 19:21) The Alter of Kelm has a Shmuess about how despite what the Shevotim wanted to do to Yosef, and all the Tzaros he went through, in the end only good came out: לְהַחֲיֹות עַם רָב (Vayechi 50:20) to save the world. The same with the tragedy of Korach. In the end, Korach will be Cohen Gadol לֶעָתִיד לָבֹוא in the future, and Korach’s Einikel, Shmuel HaNavi, was the source of two great kings [Shaul and Dovid] and eventually Melech HaMoshiach.
The Chasidim say that everything evil in this world is just a stepping stone to final goodness. Chazal say that when Dovid was enabled to kill a lion and a bear, he was being given a Siman that one day he would kill the giant Golyas and thereby save Klal Yisroel. When he saw Golyas, he was sure he would kill him, because of his Simanim.