The rebellion that Korah staged, cobbling together a diverse group whose only common cause was to overthrow Moshe and Aharon, happened at the lowest point of the exodus. The nation, under the influence of the spies, had just rejected the gift of the land of Israel and are now destined to die in the desert, never to set eyes on the promised land.
However, through the eyes of our sages, Korah was not motivated out of concern for the people, but instead by his envy of the honors given to others. He took advantage of Moshe’s vulnerability to seize power for himself.
The Talmud comments that there are some people whose lives are truly unbearable. One of these people is a person who is overly sensitive. Why would their lives be so unlivable?
To understand their perspective, imagine a person who has severe sunburn over his body, even a friendly touch would be felt as excruciating pain. Emotions can be as overly sensitive as our skin, and experiences which would be innocent or even enjoyable can be more painful than even a severe burn. With fragile emotions, they go through their lives in self-induced torment.
Similarly, Korah, in the opinion of our sages, had a distorted and inflated view of his own importance. Due to his feelings of superiority, he felt slighted by Moshe while no amount of recognition was enough to satisfy his insatiable ego. Therefore, at the first opportune time, he orchestrated the doomed rebellion and will always be remembered for his willingness to destroy an entire nation to satisfy his fragile ego.
~Rabbi Shaul