The truth is, over-shampooing is the number one reason why soft surfacing gets damaged. And really, it's no surprise as so many places now rent out machines, giving people the impression that it's an easy-peasy DIY project. When, in fact, it isn't! The main problem is, people aren't rinsing out the fibers properly, which results in a chemical residue. Not only does your surfacing remain dirty, but this residue also attracts more dirt!
Many rental machines simply don't control water output well. That results in soaked surfacing, and leads to mold and mildew growth - yuck! It's not only a gross thought, but it's a health hazard that dangerous for your family. Additionally, uneven drying times may lead to shrinkage and tearing along seams or edges.
Overuse of Deodorizers
Of course, you want your home smelling as fresh as a daisy. With pets, however, that may virtually be impossible. While Fido pees in the corner, Fifi rolls around on the floor, creating a pretty stinky sensation that's hard to ignore. Using deodorizers can result in a build-up of scented powder, something that's hard to remove with a standard vacuum.
Last, an unprofessional deep cleaning may invalidate your manufacturer's warranty. Before you run out and rent a machine for a DIY, make sure to read through your warranty to avoid a nasty (and expensive) surprise!