IMPORTANT NOTE: This article should only be used for any Mac that can go no further than macOS 10.15. All other Macs that can run Big Sur and up should follow this article to prepare a Mac for reload using a boot stick.
macOS 10.15 creates two "volumes" on installation. A "System" volume and a "Data" volume. To "wipe and reload" a 10.15 mac, you will need to repartition the drive into one volume before you reload the system.
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