One bad place to install carpeting is a kitchen. As a carpet cleaner I do not see this much but it is out there. Usually people install it in a kitchen because they want to prevent slipping or they like the warmth of carpet over tile. Even if you choose a commercial carpet it will never last long in a kitchen though. Kitchens are just subject to too much moisture, grease and food spills. So do not even think about installing carpet in a kitchen.

Another bad place for carpet is a bathroom. You normally see this in new homes where the builder has found it cheaper to just put carpet in the baths instead of tile or vinyl. Like kitchens, baths are subject to way too much moisture. Also most bathroom cleaners will bleach a carpet meaning that you have to be very careful when cleaning your bathroom. Carpet in baths never lasts long and should also be avoided.

The last place I will discuss is carpet on stairs. Unfortunately this might be a necessary evil. Carpet makes stairs safer by preventing the chance of slipping and is much cheaper than installing hard surfaces on them. Wood for example is very expensive to install on stairs because of all the necessary trim pieces. Carpet will have a short life on stairs because of the concentrated foot traffic causing wear. To improve its life vacuum it often and have it professionally cleaned often.

Overall carpet is a great flooring choice but you must remember to use it where it is appropriate.