What is the reason behind the PS4K?

[Hynad]

Mar1217 said:

Hynad said:
Since they came into the market, Sony learned that they could manage two consoles at once. If they release a PS4K, it's most likelly as a counter-measure to Nintendo's "NX".

And they know that "it'd be alright".

*cough* PS Vita, PS TV *cough*

They were still supporting two healthy home consoles during the lifetime of both.