Concrete is porous. Concrete acts as a sponge as it is exposed to water. The concrete will draw water until it is saturated or there is no more water available. Then the water will be dispersed throughout the concrete as it tries to achieve and equilibrium state. Since air is always much drier than the wet concrete so water will always seek the surface of the concrete.
Often concrete is not coated properly during construction. Sealing basements correctly will inhibit mould growth and provide a good moisture barrier. When mold spores land on a moist spot indoors, they may start growing and digesting whatever they are growing on to survive. For appearances, a concrete paint will do wonders, but a proper concrete coating is necessary to extend the life of the basement and increase the resale value of your home.
Concrete was designed for strength, not beauty. For water resistance purposes, a good concrete coating should be applied. What is often overlooked is sealing basements properly with an effective concrete coating. Remember, concrete paint is not enough to protect your investment.
Do not simply hide a problem with concrete paint; invest in a proper concrete coating, as sealing basements is most important. I do not want to raise a nasty word but Radon gas is one of the main reasons for basement sealing with concrete sealants.