As an auditor you might have planned more than one audits a day for yourself. It is not necessary that these audits will be of the same client and can have very different requirements. As an auditor it is your responsibility to go through the training document and the questionnaire before going to conduct an audit so all the relevant details can be captured in the report.
As an auditor the ultimate aim is to fill the report on the basis of observations in the store during shopping.
A questionnaire can have questions related to many intricate details which may be missed out when you are reading the training document and also while conducting the audit. If such a situation should arise then you will have no answer to that specific question and if crucial it might be the reason why a report might get returned to you and you may have to revisit the store among other things. Other things like impact on the shopper score and deduction in the shopper fee.