I'm always unsure of what a "flawed cork" is, so I'm not sure that all the potentially bad corks lead to a bad wine experience. The flaw may or may not be in a place that leads to a problem, or the wine might not be in the bottle long enough for the problem to manifest, etc. But the point is bad bottles are out there, and if you drink wine regularly, you will run across them. My own rate of clearly bad bottles is 1-2%, but most of the wine I buy is inexpensive and drunk soon after bottling.

My last bad bottle was "corked", but had a glass stopper and rubber gasket.