Comment 2 for bug 1637843

Making the deploy button disabled is IMHO going to bring more confusion due to the fact how we display nodes counts at the moment (see https://bugs.launchpad.net/tripleo/+bug/1640103)

The 'Validate and Deploy' button does not trigger any harmful operation. It brings up the summary view which provides the user with feedback on whether starting the deployment is safe or not. It is the up to the user to evaluate provided information and decide to start the deployment.