No.  Dirt is an abrasive  –  like sandpaper.  Every time you step on the carpet, you grind dirt into your carpet fibers.  This cuts your carpet, just as if you had used a knife.  Causing it to wear out faster.  Vacuuming helps, but by itself, it simply not enough.  The longer you wait to have your carpet cleaned, the more damage you do to it.  In fact, Shaw Industries, the world largest carpet manufacturer recommends cleaning every twelve to eighteen months and failure to do this voids the warranty.