The Customer Grids are a 2-D view of your customers scored with RFM.
Their intersection tells you a bit of a story about how their buying behavior compares to the rest of your customer base. They might be ordering very frequently, but spending very little.
Three different grids based on RFM
There are three different grids, each using two of the RFM factors. That means each grid views the customer in a different light.
The Recency-Frequency (RF) Grid looks at how recent and how many orders a customer has placed. This helps to segment active customers from defecting customers (top vs bottom) and loyal customers from new customers (right vs left).
Frequency-Monetary (FM) Grid relates how many orders against how much a customer has spent. This ends up comparing customers to your Average Order Value but in a more of a gradient with five different levels.
Recency-Monetary (RM) Grid looks at order sizes against how recently customers have ordered. This can help you see if customers are trending towards higher (or lower) orders sizes than in the past.
Multiple segments for every customer
Each grid has 25 different positions for a customer to be grouped into and each customer has a place in every grid. This gives you a lot of segments to work with, especially when combined with the full RFM and the Customer Grading features of Repeat Customer Insights.
That's why the Customer Grids adds Automatic Segments to the grids. These segments combine similar scores into 30ish named segments which are easier to understand and target. Customers in each Automatic Segment can be browsed in the Customer Segmenting and exported in those areas of the app.
Historic views and comparison
Every month, a snapshot of your current Customer Grids is taken and saved. That'll let you go back in time and see how the grids were populated in the past (great Scott!)
You can also compare those historic snapshots with each other or the current grids. This will let you see how your customers are flowing between the different segments. This flow can show you issues and opportunities in customer behavior that normally is hidden behind the data.
For growing Shopify stores, I recommend taking a glance at the percentage version. Growth can mask problem in the raw numbers, perhaps your Loyal customers are growing but at a dramatically lower pace than your Defected customers.
Market to your customer's timing
Figure out how long customers wait in-between purchases and you have a key component for your marketing timing. This is the basis of the Average Latency metric and Order Sequence Report in Repeat Customer Insights.