Keyboard Delay on PS4?

I play Fortnite on the PS4 but with a keyboard but whenever I build a staircase there's a delay or I can't build a staircase but when I build a wall or a floor it all happens without delay and when I play on a PC with a keyboard everything is okay with the stairs so there's no delay with it.

Why is that?

Because the PS4 graphics unit is too bad to be able to render stairs as quickly as walls or floors…