Similarly in Spanish, which has great consistency, in that if you see a word written, you pretty much know how to pronounce it, and vice versa. English is pretty bad in that department, but still much better than Chinese.

While many Chinese characters have a phonetic component (in addition to a component related to the meaning), it rarely corresponds exactly to the current pronunciation (in Mandarin).

Furthermore, you can very rarely conjure the right character out of pronunciation and and some aspect of the meaning.