Heck I found the same to be true of vagrant. Big promises, short on delivery. While mostly usable, it's definitely not as seamless across various guests, providers, and provisioners as their docs might have you think. Stray off the beaten path even the tiniest bit and expect to spend hours looking at github issues for workarounds (submitted by other users not the dev team).

My experience.

Windows guests: buggy

FreeBSD guests: buggy

Ansible provisioning: buggy

Windows support was incorporated from a community plugin. Now it's in limbo maintained neither by the original creators nor the (seemingly) lone dev from hashicorp assigned to vagrant.

They use DRM to protect their closed source proprietary plugins and it makes it a nightmare to build a version from source that works with said plugins. Building the installer is closed source for some reason.

After finally being able to run with modified source, I was able to monkey patch their paid VMWare plugin to add a capability so I could use private_network with static IP on Windows guests . I posted the monkey patch to github issues and it took two weeks for their paid plugin to be updated.

I wanted to love and contribute to vagrant, but the somewhat dishonest docs, unresponsive dev team, and DRM have turned me into a grudging user only because there are no alternatives.

Vagrant is definitely a wolf in sheepskin in terms of appearing open source and open to community collaboration.