Why didn't White Fang like being sled leader?

With the death of Lip-Lip, Mit-sah makes White Fang the lead sled dog and the other dogs' hatred of him is intensified. The extra favors bestowed on him along with the extra rations of meat given to him make the pack of dogs attack him more viciously than ever.

Being sled-leader was anything but gratifying to him. To be compelled to run away before the yelling pack, every dog of which, for three years, he had thrashed and mastered, was almost more than he could endure. But endure it he must, or perish, and the life that was in him had no desire to perish out. The moment Mit-sah gave his order for the start, that moment the whole team, with eager, savage cries, sprang forward at White Fang.