How important is customer service to you?

I saw several threads similar to this, but I think this is slightly different.

After several months of continuing poor customer service and billing, I have switched service providers for internet and cable. I made changes to my account in Feb and since then I have had to call back four times due to non-completion of the original order and excessive amounts being billed. The customer service was lackluster at best and incompetent (the original order not being completed correctly 3 times) at worst. I finally had enough and canceled the service completely. I have a feeling they assumed I would not cancel the service as it is a hassle to do so.

I was somewhat surprised the company did not do anything to keep me as a customer as I have always paid the bill. However, another part of me figured they are big enough, they really do not care about keeping one customer.

Do or would you change any service due to poor customer service? Or does the hassle of changing services keep you tied to a company?