For seven months, I lived in Santiago, Chile teaching English. It made me realize how fortunate I am to have been born speaking English because if I hadn't I probably would never learn it. English, like French is not phonetic and that drives me crazy. It's why my Spanish speaking students doubted me when I told them about spelling bees. Why would anybody stage a competition around spelling when it's sooo easy? They had forgotten for a moment their own struggles to spell and pronounce some of our more difficult English words.I cannot imagine how difficult it would be to learn English and attempt spelling. The languages that I've learned - Spanish and German - are both pretty easy to "sound out" (Spanish more so than German). This makes it easier to learn spelling and pronunciation. But English, not so much. A lot of English's "crazy" spelling can be explained by the Great Vowel Shift.
So what is the Great Vowel Shift? It is something that happened back between the years 1400 and 1600 C.E. (common era). Side note: My linguistics text book states 1400-1600 CE, but Wikipedia states this change happened between 1200 and 1600 CE. You see, languages tend to evolve over time. They change. The Great Vowel Shift is an example of one such change that has affected the way English speakers pronounce certain vowels. Evidence of this vowel shift remains in certain pairs of words. For example: please/pleasant, serene/serenity, sane/sanity. Do you hear the difference? The first word in each pair have been affected by the vowel shift, whereas the latter word has not.
So what does this have to do with spelling? At one time, English speakers DID pronounce words as they were spelled. Because spelling was pretty much already established at the time the Great Vowel Shift occurred, the pronunciation changed while the spelling did not. And that is why English has such "crazy" spelling.
Want to learn more about the Great Vowel Shift? Try starting here. You can also easily google it.