The human-readable text is very nice. However, these are not Root Causes:

* The root cause of the issue was that the Jenkins master was not able to connect to the vCenter server. ==> Why was it not?

* The root cause was a drive failed error ==> Why did the drive fail?

* The root cause was that the Slack API was rate limited. => Why was it rate limited?

These exampled from the article may be human-readable errors, but that doesn't make them root causes.

To have a root cause analysis, try asking Why five times. https://en.wikipedia.org/wiki/Five_whys