Why can't we spell English words phonetically?

Answer 1

English has a generally phonological writing system. This means that words are spelled to allow us to understand the relationships between words, not necessarily exactly how to pronounce them. For example, the word "sign" shows us by its spelling that it is related to the word "signal," even if we do not pronounce every letter in the former.

The English language has been influenced by so many other languages with differing writing systems, and for the most part, it does not change spellings to match its phonetic system.