That's one of the most common misconceptions about carpet cleaning services. The answer is: no, carpets do not get dirtier fast after cleaning them. In the dark ages of carpet cleaning, it used to be that way. Cleaning systems used to leave a lot of soil-attracting residue. However, because dirt is abrasive, every time you step on your carpet it grinds into the fibers. This creates traffic lanes that can become permanent when not properly taken care of.
Today's commercial cleaning equipment and cleaning agents, when used by trained technicians, are designed to leave the carpet fibers completely clean and residue-free, actually extending the time between cleanings and the life of the carpet.