222M Euros error - the importance of exception management

I recall many years ago (probably the late 1980's), when a woman went to a fashion store in Brussels and purchased a dress for BEF18,500 (then approx GBP240). The store assistant was new to the POS terminal, and erroneously entered an extra 6 '9's, ie 18500999999, and convinced the Customer to sign the [American Express] Charge Card sales slip.

That transaction sailed all the way through, rang no alarm bells within Store or with Merchant Acquirer, and was applied to the Charge Card account.

Warning bells then came the next day from Treasury, who recognised an extreme exposure to BEF.

As the Customer was also enrolled in Direct Debit, I had the fun and games of working out how best to reverse out the erroeneous transaction and apply the correct amount before the deadline for issuing the Direct Debit request.

Thereafter we did have a 'reasonability' check, but it did still have to be denominated in "millions" to allow for exceptional purchases such as Jet Aircraft Engines (that's another story, involving Guinness Peat Aviation at East Midlands Airport)

It's so ironic that a EUR 10 online purchase would have to go through CVV and VbV (and Mobile OTP, if it's in India) whereas such a high value EFT transaction almost bypasses exception management procedures! In a way, I attribute such incidents to standard software implementation methodologies where only the basic processes are implemented and all exceptions are swept beneath the rug as "nice to have" features that are deferred to the proverbial "next phase", which never happens in practice.