Why settlement happens
Support conditions can change because of soil shrinkage, poor or variable compaction, erosion, plumbing leaks, drainage, tree-related moisture extraction, or other site-specific factors.
How it shows up
Cracks, sloping floors, sticking openings, separations, and elevation differences can all occur. The direction of movement and the pattern across the structure are more useful than any one symptom.
Settlement versus heave
Not all movement is downward. Moisture-sensitive soil can also swell, and some structures experience upward movement or a combination of heave and settlement. Repair should follow the diagnosis.
Local context: Educational statements about expansive clay, wet/dry soil movement, and common warning signs are consistent with current guidance published for Sugar Land and the greater Houston area. They are general context, not a diagnosis for any individual property.