As a result of some area codes running out of usable exchanges, the phone company experimented with "meaningless" exchange codes. That is, there would be two letters that had no English word basis. This was done in New York State as a trial for some years. It did not work out and they concluded to go to ANC instead.
Some areas didn't mind ANC, but some objected very much so. As others mentioned, there were organized protest groups against it. In some communities, the exchange name was a badge of social status.
Although I like exchange names because of the sense of dignity and ease of memory they offer, I can understand the phone company's issues as well. Some names, like HYatt or HYacinth, are easily mispelled (HI instead of HY). Some names are pretty obscure, like SWinburne (an ancient poet). When 0 and 1 became common as the third digit of an exchange, confusion was more likely (PI1, HO0). Overseas calls become a real problem.
[TELECOM Digest Editor's Note: Over the years I have had these Chicago numbers: RAVenswood-8-7425 (which also spells 'Patrick') and HYDe Park 3-3714 and SHEldrake-0001. All, a long, long time ago. PAT]