The following quotes from the Civil Design* web site illustrates how important sound construction practices are:
(1) Wheelchair injury, asphalt failure. A small portion of asphalt failed which resulted in a wheel of wheelchair being displaced, throwing occupant to the ground, causing multiple injuries.

(2) Stairway trip and fall. Person lost balance due to irregularity of stairs and sustained injuries. Stairs were improperly constructed.

(3) Scaffolding failure. Scaffold improperly erected failed, injuring workman.

(4) Auto accident. Poor road design was contributing factor causing accident. Computer modelling was used to show friction factors.

Aren't you envious of the bees? They get it right every time.

*(www.civildesign.com/html/forensic.htm)