[lawgolfer]

All concrete will vary in color from slab to slab unless it has been a continuous pour from one batch. If it is sound and is, otherwise, level and in good condition, your only remedy is to have it painted or topped with pavers

The real problem with concrete, which I can't believe will ever show up in TV given the skill and experience of the contractors, is when it has been improperly "cured". This happens in high heat. The surface of all concrete needs to be kept damp for several hours after it has been poured and floated. All this involves is having someone present with a garden hose and, lightly, mist the surface so as to prevent the surface from drying out until the entire slab has cured. Another cause, although less likely is that the concrete mix has sat in the delivery truck for too long a time before being poured and is well into being cured before has been poured.

It very easy to know when this step has not been done. The surface of the slab will appear as white as a new bedsheet. It will have no strength and will "spall", which means it chips or flakes. Invariably, this happens when the person(s) doing the work is unlicensed and inexperienced. We saw frequently saw this in the Southwest where a contractor, whether or not licensed, picked up his laborers in the front of Lowe's or Home Depot or at an interection.