Drain tiles and protective coating materials are originally installed during the construction of a home to protect it, but these materials will break down over time. This is caused by the expansion and contraction of basement walls as well as hydrostatic pressure which is created when the ground becomes wet. As the ground expands under hydrostatic pressure, the water searches for the path of least resistance and can enter your basement as follows:
The Wall
Through the walls (block, poured concrete or other), which are porous due to the nature of the cementatious material of which they are made.
Over Footer
Over the footer because the wall and footer are poured separately
which forms a joint that sometimes allows water to infiltrate.
Under Footer
Under the footer due to extreme hydrostatic pressure caused by
ground saturation and rising water table.
The Cove
Through the cove where the floor and wall meet because they too
are poured seperately.
Cracks
Through floor cracks caused by water trapped under the floor slab.