They put out a high quality, overengineered, extremely expensive product that, by government mandate, had no competition. After deregulation it was clear that customers wanted a little less quality for a lot less money.
Bronson said what is intended with my now deleted post.
And considering the landfills that are filled with things that replaced "expensive" goods like a Bell phone—maybe the tradeoff isn't worth it?
I doubt any consumers then had heard about 'economic externalities' (in fact, I'm not sure enough have heard about it now).
You don't need to do any marketing when you're a government-protected monopoly and customers have a choice between having phone service with you, or no phone service at all.
But why put out a quality product then?
From what I understand, their network was overengineered and they generally put out a very high quality product, and didn't need to do a lot of marketing.