The problems -
Whenever sales is down for any customer, and the manager handling the account does not provide a specific reason for the same and provides the remedy for the problem..... the customer will contact me for an explanation.
I will have no clue about his account, as I will be handling many different issues and the frequency of data analysis for his account is, max to max, once per week.
Solution -
On any given day, if the sales is down by 10% of the daily average.... we should definitely share specific reason on an account level, traffic level and each product level.
The reasoning has to be data-based.
It should be clear as day and night, and he should be satisfied with the answer.
If the problem will be recurring, it will start showing in the rating for the manager.