“English spelling is notoriously inconsistent, and some have gone further, calling it “the world’s most awesome mess” or “an insult to human intelligence” (both these from linguists, one American, one Austrian). Maybe this is just because our alphabet only has twenty-six letters to represent more than forty phonemes, or distinctive speech-sounds, and some of those – notably q and x – are not pulling their weight, while j is not allowed to (see “John” but also “George”). If we gave s and z a consistent value (“seazon”) and extended this to k and c (“klok” and “sertain”), we could free c up for other duties, such as maybe representing ch, as once it did. But then there are all the vowels . . . .
How did this unsystematic system come about? And is it really that bad? Some say that there are only a few hundred deeply irregular words, but the trouble is that most of them are common…” (TLS).