Why? Are not grammatical errors and idiosyncrasies part of the data set that chatGPT is trained on and thus also a predictable set of tokens?
Such errors are rare enough that they are almost never the most likely next token. Therefore ChatGPT only makes such mistakes when it is given good reason to do so.
ChatGPT cannot reason.
How do we know they aren’t fake system prompts planted there by OpenAI to be returned to the user when people try to get them?