Your concrete should be cleaned on a yearly basis.

Spring is typically the best time of year to get it done. This way you're removing the fall and winter grime off your driveway. Keeping your driveway clean adds life to the surface. Keeping the deep pours of your driveway free of mold, dirt, and debris helps the concrete do it's job. This will help prevent cracking and chipping.

Nobody wants to spend thousands on a new drive. This is the preventative maintenance you need.