Why are there many good people who do not think they need salvation?
Many good people do not think they need salvation because they are so good they never see their need. They do not believe God has said they are sinners, so they remain headed for eternal doom. Recognizing one's sinfulness is the first step.
Les explains that many good people never see their need of salvation because they do not believe God has said they are sinners. This refusal is the first step they miss. He reviews the circles from Genesis: Adam was created with body, soul, and spirit, in perfect fellowship with God. His soul—mind, will, and emotion—was in agreement with the Creator, and his spirit communed with God. When Adam sinned, his whole personality became a sin nature, bent to sinning. Communication with God became dormant, not annihilated; the spark is still there but dead. Les uses the analogy of a car battery left with lights on overnight—it is dead. So even morally good people share this fallen condition and do not recognize their need until they accept God's verdict that they are sinners.