I downloaded the Mojave installer from the App Store and copied it to a USB stick like so:
$ sudo /Applications/Install\ macOS\ Mojave.app/Contents/Resources/createinstallmedia --volume /Volumes/UNTITLED --nointeraction
Previous to that I formatted the USB stick with the option Mac OS Extended (Journaled) from the Disk Utility app.
The problem is that when I start the computer holding the Option key it shows three options to boot from, one is my disk drive, the other is the Mojave installer in the USD stick, and there is also a suspiciously named Windows option.
If I pick the Mojave installer it reads the USB stick and shows the progress bar that appears when the systems is starting but it takes too long and it quickly stops reading the USB stick. It also doesn't show the installer app after it reaches 100% of the progress bar.
If I try to start from the Windows option I see a black screen showing an EFI error, but I have never tried to install Windows on my computer, so I'm not sure what that option is trying to do.
How long does it takes to show the Mojave installer app when starting from the USB stick?
Is it ok if the USB stick stops showing activity after a couple of minutes while the progress bar is still below 20% or 30% after the Mojave installer is selected from the boot loader?