The United States Marine Corps has a saying: every Marine a rifleman. The point is, no matter what your day job in the Marine Corps is, you’re also an infantry soldier, able to shoot at enemies. The Marine Corps, like any large organization, does a lot of things: Marines are, as part of their official duties, lawyers, truck drivers, cooks, electricians, plumbers, musicians, accountants, ceremonial guards, artillerymen, firefighters, system administrators, paper pushers, and nearly everything else under the sun.

Every one of them is also a rifleman, though, because the purpose of the Marine Corps is not to push paper, fight fires, administer systems, play music, drive trucks, etc. but to shoot guns at enemies. The Marine Corps is a particularly effective organization because they do not lose sight of this.

With this — and an experience I had the other day — in mind, I have come up with another customer service rule. Actually, it’s more of a credo than a rule:

Any retail business is, on a superficial level at least, a very simple one: The retailer purchases goods in large quantities, and resells them in smaller quantities and at high prices to customers. Whether you’re talking about a hot-dog stand or Nordstrom, this is what retailing is.

And the front line — the rifleman — of the retail business is the cashier. The cashier actually performs the exchange of goods for money on behalf of the store. Everything else the company does — advertising, market research, high-priced lighting designers to make the products look better, customer assistance, etc. — is done for no reason other than to cause the customer-cashier transaction to take place more often, and for more money to be exchanged each time.

Every employee in the company, from the CEO down to the janitor, are there to make the customer-cashier transaction happen.

Which is why it’s so disappointing when stores can’t seem to handle that transaction.

Yesterday, I was at a Best Buy store in Reston, Virginia, attempting to buy two wireless network gateways for about $100 each. I knew Best Buy would have them because they advertise heavily and at great expense to let me know that they’re the place to go for electronics.

I grabbed the gateways and headed for the cash registers. Of the ten cash registers in this particular Best Buy, two were in use. A total of twenty people were in line.

When a few more people had shown up, and there were twenty-five people in line, the door greeter — he’s there to stop you stealing things — called on the squawk box for ‘all cashiers to come to the front.’

When he said this, two Best Buy managers who’d been milling around trying to solve some problem the cashiers were having actually started walking away.

A few minutes later, more than thirty people were in line, and no more cashiers had shown up. One of the managers wandered over again and directed a couple of customers to a cash register at the customer service desk, where they could buy things as long as they were paying with credit cards. The manager then wandered away again.

A few minutes later, more than thirty-five people were in line — the lines extended well into the CD racks now — and one of the two cashiers announced that her cash register had broken down entirely, and that everyone would have to move to the other line.

While all this was going on, there were, within my line of sight, about ten Best Buy employees, including the two managers and the guy by the door. Others were leaning against display cases, explaining things to customers, repairing computers, etc. The place was not short-staffed.

It is interesting to note that the solution to this problem — that Best Buy could not manage to fulfill its basic function of taking money from people in exchange for gadgets — was not for the nearby employees to start taking money, but for them to call for some separate class of employees, the cashier-priests, none of whom appeared to actually be in the store.

Now, it’s actually more important for every employee to be a cashier than it is for every Marine to be a rifleman. I mean no disrespect to the Marine Corps, but it is possible to kill people by other means than shooting them with rifles. It’s not really possible, in actual bricks-and-mortar retail commerce, to sell things without having someone personally take cash or some other form of payment from the customer.

When the customer is standing in line with merchandise in one hand and his wallet in the other, pretty much all the retailer’s costs have already been incurred. The customer has been enticed to come into the store; the merchandise has been stocked; the rent on the store and the electric bill has been paid; the employees have all been hired. Now it’s time to put some figures on the other side of the balance sheet.

If you’re a retailer, at this point you have a lot of money invested in making this sale. If you don’t make it, you lose everything you’ve invested, and you can never recover that money. At Best Buy yesterday, one customer left a $2,000 television set sitting on a cart in the middle of the aisle and walked out. Another hurled two wireless gateways to the ground and stalked off. A number of others stuffed their would-be purchases in the CD racks and left.

Not only did Best Buy not get the thousands of dollars in revenue for sales that they had already all buy made, it’s likely that Circuit City or another of Best Buy’s competitors did. And the next time any of those customers think of going to Best Buy, it’s a fair bet that they’ll think twice — and a good portion of them will, like me, tell others what a horrible experience it was shopping there, for the benefit of any friends who may somehow not have noticed this for themselves. All because Best Buy is incapable of staffing cash registers.

So here’s the customer service rule, for easy inclusion in your Tinotopia scrapbook. It’s similar to #3, “Don’t make customers work for the privilege of giving you money”, but more specific:

• Your highest purpose is to take the customer’s money. The entire reason for the existence of any retail establishment is to take money in exchange for goods; all your other activities are merely in support of the cashier’s function. Your systems must be designed so that any employee in your store can serve as a cashier, if needed. If this means letting shelves go un-restocked for a while, so be it. If it means not assisting other potential customers with their purchases for a while, that’s fine. If it means not answering the phone for the next half-hour, then don’t answer the phone. Better to let those potential sales go unmade than to throw away the sales that are already waiting in line.