Why do wounds heal and how does scar tissue form?

The answer

Wound healing occurs in four overlapping phases. First, blood clotting stops the bleeding within minutes. Then inflammation brings white blood cells to fight infection. In the proliferation phase, fibroblasts lay down collagen in a rapid, disorganized pattern to close the gap quickly - this becomes scar tissue. Finally, the remodeling phase (lasting months to years) gradually reorganizes the collagen. Scar tissue has only about 80% of normal skin's strength and lacks hair follicles and sweat glands, which is why scars look and feel different.