Customer service is something for which the enterprise is born. Its vision should be ideally to create value for its customers, build relationships and increase that value creation over time. To that effect, customer service division of a company plays a pivotal role.
In fact, I find it a bit surprising that many companies treat departments such as warranty repairs, customer support and customer relationship as cost centers. To me, these departments can provide the foundation over which the entire company stands. They are the face of the company with whom the customers interact. They should be as efficient, as trained and as friendly as possible. They have the potential of making or breaking it for the company in the long run.
In fact, their behaviors and actions can lead to sustained relationships with the customers, the word of mouth/viral publicity and sustained revenues for the company.
So, treat customer service as profit center and not a bare cost center. The dividends would be much higher. And do note, this simple mentality change can lead to how you perceive them, how you allocate investments, how you train them, what culture you nurture and the overall strategy.