What constitutes a bad camera

One that doesn't do what you want it to do.

The Olympus E-30 if you want clean shadows. The Olympus E-510 if you want a huge viewfinder or AF at night, or to shoot in the rain. Micro Four Thirds if you want predictive AF. Most Canon DSLRs if you want good jpegs. A compact if you want great image quality or narrow depth of field. FX if you want portability. An OM-1 if you want autofocus.

All of these are great machines if you want to do what they do. If you don't then they're not.