I've written about how every customer is shown in the Customer Grid previously but haven't really talked about the why.
When you're segmenting customers, everyone should be in a segment.
Normally you'd hear about "filtering" as a way to segment customers, as in "these are customers who have ordered 5 times". Filtering always creates a second segment too, customers who were filtered out. You end up with the customers who matched the filter and customers who didn't.
This works the same no matter how complex your filter expression is. You could filter customers to see who has a name that starts with a vowel, a surname that rhymes with ITH, who lives in Spokane, who have ordered twice in the last year...
You'll always have a segment of customers who matched and a segment of customers who didn't match. Even if there is no one in a segment.
In Shopify's customer filtering, they just don't show the customers who didn't match. If you want to see them, you have to run the filter twice, once with a positive and once with a negative. e.g. customers who have ordered 5 times, then customers who have NOT ordered 5 times.
More powerful segmenting tools will show you all customers and which segment they were placed in. In other words, they run all of the filters for you so you can get a better view of your whole customer base.
Back to the Customer Grid.
Since it's a form of customer segmenting based on RFM and RFM itself scores every customer, the Customer Grid will show all customers.
This means it becomes possible to track how customer behavior shifts over time.