Consensus and documentation of product adoption metrics terminology
## Summary
Groups across GitLab (product, data, product analytics, customer success, sales) all use terminology related to product adoption and engagement. We should agree on SSOT definitions for vocabulary and which measurements are being represented and reported to the business.
## Example
As an example, the Product Intelligence team defines self-managed Service Ping adoption as the number of production instances reporting a payload in the last month ([currently 67% - sisense](https://app.periscopedata.com/app/gitlab:safe-dashboard/943216/Operational-Data-Coverage?widget=14184710&udv=0)). Whereas, the CS team defines self-managed Service Ping adoption as customers reporting Service Ping data **and** meet a minimum activity/engagement threshold¹ ([currently 55% - sisense](https://app.periscopedata.com/app/gitlab:safe-dashboard/943216/Operational-Data-Coverage?widget=13138449&udv=0)). However, we are both reporting "Service Ping adoption" to the egroup, which could cause confusion.
_¹CS Service Ping Adoption = the percentage of customers who have at least 1 production instance that has sent us data for `CI Pipelines Run` & `Git Operation Performed` in the last full month for self managed._
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