This was years ago but something made me think about it today.
Everywhere I’ve worked (since age 15) pronounced it “F-EYE-foe”. Well a few years ago I started at a new place and the training manager was like “we FIFO our inventory” but pronounced it like “Fee-fuh” and I was like “…huh?” She looked HORRIFIED and was like “you’ve been a barista for a decade and you don’t know what ‘fee-fuh’ is?!?!?” And proceeds to say “well ‘fee-fuh’ stands for ‘first in first out’” at which point I’m like OH, FIFO, yes I’m familiar, we just pronounced it ‘f-EYE-foe’”. For some reason she felt the need to be like “well I’ll explain anyway in case you don’t get it” which wtf, but that’s not relevant.
That was the ONLY time I’ve heard FIFO pronounced that way, so I’m wondering if that’s a common thing anywhere? Maybe the way we pronounced it is a regional thing? Idk