GENERATING A HYDROPHOBIC STRUCTURE

That's step number 2

A denser, more impervious microstructure of the concrete may be supplemental, but plasticisers do not create a pore and capillary free concrete. Given the crucial role that water, chlorides and other harmful water-borne chemicals play in many deterioration processes, their ingress into the concrete must be completely prevented. Therefore, filling and sealing the pore and capillary structure becomes necessary and is the second step. 

As for water does not care from what side to enter into concrete, the PROTECT concept provides water repellence for the entire concrete: Adding hydrophobic admixtures during concrete’s mixing process ensures holistic and permanent protection against water penetrating into the concrete structure:

Since the reaction takes place inside the matrix of the concrete, the hydrophobic agent becomes an integral part of the concrete mass and thus cannot be removed or worn off later on.