Some call centers tend to treat you, the caller, like a document. You call up with a simple piece of information (e.g. “You’ve over billed me this month”) and then you get bumped between different staff members like an unwanted email. The thing about email is that it doesn’t get extremely pissed off if you keep it waiting for ½ an hour.
This ‘treat the caller as a document’ practice is expensive for the call centers too. I can understand sacrificing customer experience to save money (that’s what call centers are about after all), but doing this and costing yourself money at the same time is unforgivable.