Cracks

The type and pattern in your cracks reveal the cause, including hydrostatic pressure,  expansive soils or frost heaves

Bulging

Water saturated soil is heavy and causes an immense amount of pressure inwards, especially in the middle - bowing must be addressed before a failure occurs

Seeping

Those cracks grow, expand and allow water in. If you're seeing water on one side of the wall it is likely very close on the other side.

Musty, Mold, Dampness, Chalking

Standing water and water entry are obvious grounds for mould, mildew and health concerns - on top of structural integrity issues