5. Backwards-Compatibility
Oh, business decisions; you can see a lot of the cogs turning behind the way these machines operate once you're looking in the right direction. Backwards-compatibility was something Sony did a weird job with on the PS3. Only a select few units at launch could play PS2 games, before they faded that functionality out whilst leaving the ability to play PS1 games going forward. On PS4 it's even more restrictive as nothing transfers over - a good way to be forward-thinking, assumedly - however all that is just so Sony can 'force' you into using their Gaikai streaming service PS Now; which would be a good idea if it wasn't 1. Laggy as hell and 2. Stupidly expensive. For all the bells, whizz-bangs and whistles the new machines are trying to bolt onto the core idea of just being a games machine, having respect for your consumer's library is one of the biggest oversights. Although it's probably something hardwired into the running of the machine that doesn't allow for older discs to transfer over now, inserting an old game, being then presented with a unique/discount code and redeeming it in the store would be a fantastic recompense instead.