What does McMurphy's "haggard, puzzled look" indicate about the evolution of his character?

McMurphy comes into his confinement all upbeat and devious. He soon sizes up the situation and decides he can wreak havoc in this situation. As he is worn down by Nurse Ratched, he begins to lose his vigorous attach on the system; he is tired (haggard) and often puzzled when his plans do not go as he expected.