Electrical condition reports

I think as a rule the general public are probably unaware of the recommendations that an Electrical Installation is Tested and Inspected every 10 years or every change of occupancy or ownership. Why does the I.E.T recommend this? Various reasons, electricity is generally supplied at 50Hz which means that it constantly vibrates, over time this can cause the terminal screws in sockets, switches, lights, and junction boxes to become loose which causes arcing and a build up of heat.