How many ways are there to spell the sound ō (as in l’eau) in French? I once read that it was over 30, but it might have been a tongue-in-cheek joke, like "ghoti" as an alternate spelling of "fish"[1]
As far as I know, there are two: 'o' (as in 'bon') and 'eau' (as in 'beau').While that's one more than it should have been necessary, it's not that bad I think.
But I have learned I had a misconception about what a phonetic spelling is. I had thought that a phonetic spelling had the property of every sound in the language having one way to spell it, but that is not the case; instead for every grapheme there is one sound.
As a native English speaker, learning a little French (after German and Latin) opened my eyes to the horrors of English. Really French is very tame in comparison.
Forgot about 'au'; I think the x and t in these examples are misleading, they are just part of the general rule that final consonants are not pronounced (though there are exceptions to that rule).
[1] https://en.wikipedia.org/wiki/Ghoti