Delaying elimination when necessary might also lead to long-term medical problems including mineral deposits that may clog the urethra so that your pet might not be able to urinate at all. That could be life threatening. Worst of all, your cat might just refuse to use a dirty litter box at all and that means you'll be finding your pet's surprises around your home. Once that behavior starts, it's tough to correct and control the problem. In fact, if your pet falls into this pattern of behavior, you may have to work hard to retrain your cat to use the litter box again.
Bacteria pass with fecal waste which frequently contaminates the litter.
Since most cats urinate in the same general area in the litter box, they add moisture to support the growth of bacteria. When your cat returns to the box, he or she can easily pick up the bacteria while sniffing and scratching around to create a new spot to deposit waste. That bacteria can get on your cat's paws or body and may result in an infection. This is especially threatening if you have a multiple-cat household. A potential hazard in a multi-cat household is the spread of disease from one cat to another through the use of a common litter box.