IzzyBoot - Fails with message "Failed to open OS X Installer," or "The macOS installation couldn't be completed"

If you get a screen with a dialog box that looks like this (the specific wording changes from version to version of macOS), reset the PRAM

How to reset PRAM

Reset PRAM

1. Locate the following keys on the keyboard: Option, Command (⌘), P, and R. You will need to hold these keys down simultaneously in step 3.
2. Turn on your Mac.
3. Immediately press and hold the Option-Command-P-R keys. You must press this key combination before the gray screen appears.
4. Continue holding the keys down until your Mac restarts, and you hear the startup sound for the second time.
5. Release the keys.