Tarrant County sits on expansive clay. It swells when it's wet and shrinks when it's dry, and in a typical year it does both several times. A slab poured directly on that soil without a compacted base is going to move, and concrete doesn't bend. It cracks.
A properly built patio starts below the surface: topsoil removed, subgrade compacted, a layer of crushed stone compacted again, and then the slab. Rebar set on chairs in the middle of the slab, not lying on the dirt, ties the concrete together so that if a hairline crack does form, it can't open up or offset.
Control joints are the part homeowners ask about most. They're not decoration. They're planned weak lines cut at the right spacing and depth so the concrete cracks inside the joint, where you'll never see it, instead of across the middle of the patio. Spacing depends on slab thickness, and cutting them too late or too shallow makes them useless.
Finally, curing. Concrete that dries too fast in a 100-degree August afternoon loses strength and shrinks unevenly. We time pours, keep the surface damp when needed, and tell you honestly how long to stay off it. When you get quotes, ask about base depth, rebar, joint spacing, and cure. If the answers are vague, the price is too.