In So Cal we had the main kitchen drain severed by the Northridge earthquake. The house went back and forth and the drainpipe split but ended up with both pieces lined up perfectly. We noticed a damp area on the concrete walk several times over a few moths before we noticed the paint flaking off the stucco. And the wet baseboard on the inside.
Turns out it would not leak except with the pressure of the dishwasher dumping. We usually run the dishwasher only a couple of times a week so it took a while to get bad enough to figure out what it was.
The ins agent sent a leak detector who marked the spot to open up the exterior wall and was only 1" off! The insurance paid for everything to be repaired and I actually made back part of my deductible by repairing the interior baseboard and painting a wall myself.