Carpet Wear

I took a few close up photos of a ten year old carpet to illustrate carpet wear. On the left is carpet near a corner where there had been little foot traffic, still exposed to light, vacuuming and all around use, just not as much use as the carpet on the right that gets walked on several times a day. You can see that carpet that gets used more starts to  unravel, it lays flat and doesn't have the same feel as the rest of the carpet. In traffic patterns where carpet has been worn out much more then the surrounding carpet, it can still be cleaned, but will never look and feel like new again.

Ferndale 98248

When is it time to replace the carpet?