Deleting iCloud account is the same as erasing your Apple ID along with all the related data, like photos, backups, contacts, and purchases. When you delete, you lose the ability to sign in, and the data is not recoverable. It’s a one-way decision reserved for those who no longer wish to use any products of Apple Inc.. If you deactivate your iCloud account, this is a temporary lockout from access. Your data is safe, and reactivation of the account is possible by signing in. Deactivation helps if you intend to stop using iCloud temporarily without the risk of permanently losing your data.