A native speaker of American English (as of any other language) can make a mistake in pronunciation simply because of their ignorance of the word family to which the mispronounced item belongs. Thus, for instance, on today’s installment of the NPR program “Morning Edition” a reporter mispronounced slavishly to rhyme with lavishly, evidently unaware of the fact that the adjective slavish is derived from slave and has the primary meaning ‘of or characteristic of a slave or slavery’.

Pronunciations that are at variance with the established norm are typically to be explained as arising from ignorance of one’s language in the round, which in the digital age is clearly to be ascribed in turn to a paucity of book learning among speakers who otherwise pass for being nominally literate.