The following is from Quora, posted one year ago.
What are the disadvantages of teaching Chinese using Pinyin instead of learning all those Chinese characters?
Somnath Mukherjee answered: MSc. from Dr. C V Raman University
There are a few disadvantages to teaching Chinese using Pinyin instead of learning all those Chinese characters.
Pinyin is not a perfect representation of Chinese pronunciation. Some sounds in Chinese cannot be represented by Pinyin and some sounds in Pinyin can be pronounced in different ways depending on the context. This can make it difficult for learners to develop accurate pronunciation.