We hear this often and normally the person trying to remove the spot did not select the right carpet spot remover. Most don't realize there are different classifications of spots and stains. There are two basic types, either alkaline or acidic with the most common being acid based.
First we need to understand the difference between a spot and a stain. The simplest answer is time. A spot simply has not dried and set in yet while a stain has had time to set into the fibers of the carpet. This is why it is always easier to remove a spot before it does become a stain.
With most soils being acid based you would need to use an alkaline based carpet spot remover. The reason is these are opposite and we all know opposites attract. So using the alkaline based chemicals they will attract the soils which are acid based.
This being said, the first product to try is an alkaline based carpet spot remover. Apply to the soiled area and let it dwell or sit for a few minutes in order for the chemical to start breaking down the soils. Next, blot with a clean white towel so that no colored die from the towel gets transfered to the carpet.
I suggest applying the carpet spot remover again and this time after a few minutes agitate the spot from the outside toward the center as not to spread the soiled area. Blot again.
This should take care of removing most spots and stains from your carpet. However, there are specialized carpet spot removers such as P.O.G (paint, oil, grease), ink removers, and even red dye removers that are designed for specific soils.
Hopefully you now have a better understanding of which carpet spot remover you should use.
Take a look at our list of carpet spot remover.
