While Oscar Wilde would undoubtedly have something witty to say about that, I guess it's a matter of stress: if you read it as a word and assume stress on the (invisible) first vowel, it's almost inevitable: juh-cof.
Language is not very deterministic. An unknown word can remind you of more than one other word, which can influence the way you pronounce it, certainly in English where pronunciation is so irregular. That’s not a fact of course, just a possible factor.
There is a very, very small difference between placing a slight break in the middle of the acronym as J-COF or as JC-OF, because there's a major unwritten vowel sound after J in any case.