Pet urine is generally left at the same place on the carpet over time and the odor and stain can accumulate, and you will need pet urine odor removal services. Since it is liquid, it penetrates the carpet backing and even the flooring underneath.
Even when it dries out, pet urine crystallizes and stays within the carpet and surrounding materials. Pet urine smells, particularly when deposited at the same place in the carpeting, and permanent until correctly removed.