The ability to undo a problematic install should be mandatory, but in too many instances it is not. That's because software developers are always operating under the assumption that the latest version is the greatest version, when it may not be. This is especially true in the smartphone and tablet world. There is no rollback to be had for anything in the iOS and Android worlds.
Until the day comes when software developers start releasing perfectly functioning, error-free code, we need the ability to go backwards with all software."
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