Customer service is important for retaining customers and ensuring they are satisfied. It involves promptly helping customers, maintaining regular contact, and making it easy for them to get assistance. Key aspects of good customer service include being efficient, reliable, and treating customers with acceptance, empathy, and respect. Providing value, keeping promises, and giving customers a reason to return can help build trust and loyalty. Most customers leave due to poor treatment, so customer service should focus on genuinely helping customers.