What is the typical effect of developer oxidation on film quality?

Developer oxidation typically leads to film fogging due to the over-reduction of silver halides during the developing process. When the developer oxidizes, it can produce additional by-products that reduce the contrast of the image and create a cloudy, unclear appearance in the film. This fogging occurs because the oxidized developer can continue to reduce unexposed silver halide crystals, resulting in a veil of density that obscures the image. Consequently, instead of achieving a clear and defined image, the film becomes less usable. Understanding the effects of developer oxidation is crucial for maintaining the quality of images produced in photographic practices.