Minikube requires that VT-x/AMD-v virtualization is enabled in BIOS. To check that this is enabled on OSX / macOS run:
sysctl -a | grep machdep.cpu.features | grep VMX
If there's output, you're good!
Once in a while, you may need to cleanup resources (containers, volumes, images, networks) ...
// see: https://github.com/chadoe/docker-cleanup-volumes
$ docker volume rm $(docker volume ls -qf dangling=true)
$ docker volume ls -qf dangling=true | xargs -r docker volume rm