Hopefully once the full suite is finalised and released as Office 2015 'if' its released as a standalone product (pay once). Though I'm not sure if going forward we are looking at a Office 365 sub requirement for Office.
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That won't happen. All software vendors are moving towards it, allowing them to finally tackle the rife software piracy.
They are but the real reason is that it becomes a constant revenue stream. It's a profit thing not a piracy thing. It's all about tying the customers to a subscription by the short hairs so they are stuck and have to pay. IMO software subscriptions are just a tiny step above a protection racket, (it sure would be a shame if you couldn't access all of your records any more. As long as you keep paying whatever we ask you can open those files you need for the audit. )