Containers offer not much benefit if you're cloud native - you already have VMs and heaps of automation APIs.
When you have a large scale platform with millions of users and you need to add / remove / change services at some marketing teams whim
I don't have hands on experience with kubernetes and a quite a bit skeptical because of its supposed complexity. Would be interested in success stories though where kubernetes magic was the much needed secret sauce.
Containers offer not much benefit if you're cloud native - you already have VMs and heaps of automation APIs.