Why run R on Kubernetes?
Kubernetes is a free and open-source utility to run jobs within a computer cluster. It abstracts away the servers the jobs are running on so you need only worry about the code to run. It has features such as scheduling, auto-scaling, and auto-healing to replace nodes if they breakdown.
If you only need to run R on a single machine, then its probably a bit OTT to use Kubernetes, but if you are starting to work with multiple Docker containers and/or VMs it gets more and more attractive to have a way to easily orchestrate them.
Kubernetes works via Docker containers, so if you are already familiar with using Docker for abstracting away code environments, it should be a short step up to abstracting away the computers those Docker containers run upon.