Continuity mistake: When Steele is falling down the cliff with Jenna's bandana in his mouth, right before he hits the bottom, the bandana turns white.
Continuity mistake: While Balto is running the race, Boris is seen jumping around on a fence, cheering him on. Throughout the race, that fence changes from wobbly and dark brown to stable and light brown.
Continuity mistake: When the bear falls through the ice, it leaves a gaping hole. Once Balto slips under, an overhead shot reveals that the hole that the bear left in the ice is gone.
Continuity mistake: When Steele and his trio of dogs are mocking Balto in the alley by howling, in the shot where they see Balto growling at them and stop, the purple/gray dog's back stripes are gone.
Answer: He has an arrogant, power-hungry personality. As the situation with the medicine gets worse, he doesn't want to lose admiration from the humans and other dogs.