Will bruising lead to scarring?

Usually not: A bruise is bleeding under the skin and does not scar. If however you have a large bleed like a hematoma it can calcify if it is not drained.

Not usually: Bruising will not lead to scarring unless associated with fat necrosis or underlying tissue damage which is possible. Extensive bruising may contribute to deposition if hemosiderin pigment in the skin causing a dark discoloration.

Unlikely: Bruising usually describes a process which damages the underlying muscle and soft tissues without breaking the skin. Bleeding from capillary damage can cause the discoloration seen with the injury. For the most part, this does not affect the dermal layers substantially and therefore does not lead to scarring. If the trauma was significant enough then both bruising and scarring is possible.