I don't agree with that at all, permanent price cuts seems to be exactly what affects how well a system does with a successor. After all, who would buy a $269 PS3 when they could get a $399 PS4? The price difference wasn't enough for the PS3 to keep selling.
PS1 shipped another 29m units after the PS2 launched, it's last price cut was to $49 in May 2002.
PS2 shipped another 48m units after the PS3 launched, it's last price cut was to $99 in April 2009.
PS3 shipped just 7m units after the PS4 launched, it's last price cut was to $269 when the super slim launched in September 2012.
PS3 price didn't go low enough and didn't get a cut after the PS4 and thus it had terrible legs post-successor compared to previous PlayStation systems.
A PS4 that gets an official cut to $199 will sell a LOT more after the PS5 is released, then a $299 PS4 will.
But it's not only due to price point. PS2 sold a lot post-PS3 launch because Sony messed up big time with the PS3 launch. PS3 sold less post-PS4 launch because Sony got everything right with the PS4 launch.
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