Evan Schuman's StorefrontBacktalk

But there’s also the very real hesitation for an early-stage technology to touch POS. They’ll have to connect eventually, but a third-party that enables such mobile experimentation without touching the crown jewels is compelling. Senior management who would easily approve such projects will take much longer with potential POS impact.

One way to deal with mobile POS payments is to not deal with it. In other words, sidestep the issue. Starbucks, for example, did a wonderful job with this approach. Months after distributing its mobile application long before it could do anything useful (like obtain coffee), the chain unveiled its mobile payment process.

It’s actually quite clever in its simplicity. The hard part of the tender process is handled the old-fashioned way, either through a magstripe swipe in a store or through a standard secure payment form on its site.

Once that’s done, all the mobile app does is display the Starbucks Card’s barcode and it debits the card. In the same way that a Starbucks Card is nothing more than a way to hold the barcode, its app makes the phone just the same. So it feels like mobile payment, but it doesn’t get within light years of touching the sensitive POS system.

Carlos Cherubin, CIO of the 311-store DSW footwear chain, said the fear of the POSing issue is especially prominent with the many chains that are using older POS architectures, true legacy systems. “When you get into customizing those systems, that’s where you really add complexity,” he said.

“Especially in those shops that don’t have a lot of POS capabilities, they may be skittish about messing with their POS systems specifically because it is legacy, because it is so very touchy,” Cherubin said.

POS systems are in that small group of IT systems that are so mission-critical, they require extra special care. Few systems can cause so much damage so quickly as a POS outage, something that could temporarily make all sales difficult if not impossible.

Although not nearly as dangerous, Cherubin pointed to the one system that gets even more fear and top-level attention than POS: payroll.

Although a payroll problem doesn’t directly impact revenue (indeed, the vast majority of customers will likely never hear about even a relatively prolonged payroll problem), it will directly impact the wallets of a chain’s senior execs and every person they work with. Logic doesn’t win the day when the CEO’s salary doesn’t get deposited.