Because American Giant's supply chain can be traced all the way back to the US cotton fields, with fabric being specially woven and dyed for it, getting a new shipment of raw materials wasn't as simple as making a phone call and waiting for an overnight delivery.

BBC: American Giant: The problems of being an overnight success

The system is also used in cricket as a commentary aid to determine if a delivery would have hit the stumps in lbw decisions, but this is not available for umpires to call upon.

BBC: Premier League in Hawk-Eye trials