well, when you know how to pronounce a word, or are told a word through speech, you are familiar with it as a sound. being able to take characters and turn them into sounds is a transformative process that has rules and such, yes, but when they are encoded into sounds, trying to get them into text doesn't necesarily have the same amount of information. The distinction between c,s , k and q just turn into s and k sounds, which need to be sorted into c,s,k and q letters.

Quota and Cualquier have data loss. you need to choose which letter the K sound turns into, and the rules are gone at that point.

Otherwise you would never need a dictionary to spell things, because it would be orthographically perfect. If you knew how a word sounded, it would be a 1 to 1 mapping.

There are non-romance languages that work like this, turkish, germanic languages, and I assume, Indonesian and Malay. Ironically, despite being the source of romance languages none of them (maybe romanian?) are able to have orthographic consistency.