Because it let me replace Ansible playbooks with a sensibly designed YAML syntax usually needing 40% the number of lines, and got my deploys down to a roughly constant 6 seconds regardless of the size of the application. Kubernetes let me finally stop thinking about deployment, I can get new apps online in 5-10 minutes or less.

Don't even get me started on monitoring.. k8s murders everything else here

I'm in a team of 1 but using it because my product is based on spinning up dedicated services for users on demand, so it works well

It gives you automatic failover and decent-ish (at least when coupled with Rancher, naked k8s is nuts) management compared to a couple of manually (or Puppet) managed servers.

A well implemented mini cluster can and will save you so much time in later maintenance and deployments.