Asphalt is very porous and if inspected under a microscope you would see tiny holes that go all the way through the asphalt. Without regular protection (sealing), water will penetrate the asphalt and weaken the foundation under your driveway – leaving your asphalt without the support it needs.
The true purpose of sealing an asphalt driveway is to waterproof the asphalt. However, its not all about protecting the asphalt – we are protecting the foundation below the surface as well.