Here (Pittsburgh) the vowel in "down" or "town" is a monophthong instead of a diphthong like it is pretty much everywhere else. I wonder if part of the reason

Here (Pittsburgh) the vowel in "down" or "town" is a monophthong instead of a diphthong like it is pretty much everywhere else. I wonder if part of the reason for the diversity of regional accents in English is because pronunciation is more loosely encoded than in languages that have more vowel symbols or modifying marks, or strict phonetic pronunciation. Written English doesn't really provide many strong indicators that a particular pronunciation isn't standard.