Peter Carefoot, supply chain development manager at the Co-op Group, says: "At the end of the day there were people at Sainsbury's who felt that the risk was worth taking. We looked at automation 12 months ago and decided it was too risky.
"The trouble with the automated route is that you put all your eggs in one basket. If the system does not work there is no back-up and you are stuck; you can't go round and manually pick."
Robert Brent adds: "It sounds like the management did not understand fully what it was trying to do. Someone must have realised that what they were trying was not really feasible.