There may be a friendly Spar wherever you are, but there aren’t many happy investors in the supermarket group right now. To see why this is so, consider a cautionary tale, barely eight years old, of another retailer gone wrong.

Back in 2014, Woolworths CEO Ian Moir told shareholders that for R21.4bn, the board would "create a leading southern hemisphere retailer" and "become one of the top-10 global department store operators". All shareholders had to do was give their stamp of approval to the purchase of David Jones, an iconic Australian clothing retailer...