i read about linear cryptanalysis and about S-Box that there is not any ideal S-Box (ideal S-Box is a random S-Box in another words S-Box that bias of input and output bits is zero) then i read about implementation of S-Box in this post and understand that S-Box is implementing with Lookup tables,then read this post (e-sushi's answer) about non-linearity and randomness aspects of S-Box:
And you can trust in the fact that the chances that you’ll manage to create a good s-box randomly by using your current criteria are very minimal… very, very minimal!
but i don't understand that why is not there any random(ideal) S-Box? why can't lookup tables implement a random S-box? what is restriction(limitation) for it?