Fixing "missing architecture" errors in Xcode's Organizer

Tip of the day: you want to build a new version of your application for submission to iTunes Connect. After archiving your application in Xcode 4 and hitting the Validate button you get the following error in Organizer: executable is missing a required architecture. What could be the cause?

The reason is simple, you are validating an archive which is missing a required executable code for armv6 processor? How could that be. If you don't pay attention at your Scheme definitions, we end up trying to compile your application for the simulator. In that case, submitting this archived application to the App Store will result in this warning. Make sure that any scheme you use in Xcode for iTunes submission refer to the physical device.