Late Orders from Clicks in Past X Days
Customers may click on an ad today and end up buying the product several days or weeks later. However, Amazon will not attribute these orders to its respective clicks indefinitely.
When considering performance metrics for keywords or search terms (such as the number of orders, conversion rate or ACOS) you should keep in mind the following attribution limits for Sponsored Products and Sponsored Brands (SB):
Sponsored Products - Attribution up to 14 Days
Sponsored Brands - Attribution up to 14 Days
How is this important for the aggregate PPC Overview?
Depending on how much time your customers take before buying a product after they click your ad, all sales related metrics will tend to look better for SB than for SP.
In other words:
Sales for SB might be higher than for SP
Conversion Rates might be higher for HSA than for SP
ACoS might be lower for SB than for SP
Double Check Sponsored Products Keyword Performances
Especially in the case of Sponsored Products, it can therefore always be worth double checking any seemingly bad keywords before setting them to negative.
If common sense suggests a certain keyword is very much relevant for a given product, even though it is displaying a negative Performance after x clicks, you may want to consider giving that keyword some more time.
After all, it may already have led to sales, but from customers who, for example, might save a lot of products in their basket before buying them at the end of the month.
Optimization Timeframe - Exclusion of Recent 14 Days
When analyzing your PPC performance in Sellics, you can simply click on the "set optimization time-frame" button to quickly exclude the last 7 days from the timeframe (or 14 from SB).
This way you can make sure you are only viewing KPIs where the maximum of possible sales have already been attributed to the respective clicks: