All immigration and visa applications are processed by humans. All humans make mistakes.
This is why an officer can make a mistake when processing your application.
Some mistakes may seem minor – like misspelled name or date of birth. However, even a misspelled name may take lots of efforts and time to correct, if the typo is discovered too late – you will have to enter into correspondence with the processing office, and you know very well that their response can take weeks or sometimes months. And if you do not notice a typo until a visa is issued (or, even worse, until you receive your immigration papers upon landing in Canada), it will be much more difficult to correct it.
Other mistakes may lead to consequences that are much more serious than just processing delays – including application refusal. Cases are known when an officer misinterpreted a supporting document and made a negative decision based on his foundings. If, for example, you see in your GCMS notes something like “PA did not enclose proof of her eligible work experience”, while you are 100% sure that you did, it’s time to raise alarm and to remedy the mistake as soon as possible, since ineligibility will lead to a refusal.
Though such mistakes are relatively rare, one cannot guarantee that it won’t affect your particular application. Consider requesting GCMS notes to be on a safe side.