Why should large concrete slabs be laid with expansion joints so that they are not touching?

Large concrete slabs should be laid with expansion joints to accommodate the natural expansion and contraction of the material due to temperature fluctuations. Without these joints, the slabs can experience cracking, warping, or buckling as they shift. Expansion joints allow for movement while maintaining structural integrity, ensuring the longevity and functionality of the concrete surface. This practice minimizes maintenance costs and enhances safety by preventing surface failure.