A Word on Warranties
Talk about mind-numbing. Carpeting carries an insane number of possible warranties, including five- and 10-year options, matting and crushing warranties, and guarantees against stains, wear and even overall appearance. In general, the better quality the carpet, the more coverage you're offered via warranties, stain protection and the like. However, never purchase a particular carpet solely because the warranty seems really great -- because most warranties actually offer little true coverage [source: Carpet Buyers Handbook].
For example, the most common warranty is a "wear" warranty. Manufacturers offering these typically define "wear" as a bald spot, while many homeowners consider a carpet to be worn as soon as it loses its original appearance. Similarly, a crushing warranty may state that if the pile height can be restored to a certain degree, there's no issue. But most carpets' pile can be restored through hot water extraction and a pile rake (even though it will be crushed again once you walk on it), so manufacturers will say the warranty doesn't apply [source: Carpet Buyers Handbook].
The most common carpet complaints aren't for manufacturing defects, anyway, but rather for improper installation. These complaints should generally be taken to the retailer; before you purchase a carpet, inquire what recourse you have if you're unhappy with the installation.