When one customer matters too much

Customer concentration is the extent to which a business depends on a small number of customers for its sales. Revenue share is a useful starting point. The deeper question is what would change if a particular customer paid late, bought less or left.

A relationship can support steady work, help a team plan its schedule and reduce repeated selling effort. The same relationship can absorb capacity or create commitments that are difficult to unwind. Calling it either an advantage or a risk before examining those effects misses the decision.

Start with what the customer leaves

For an invented example, a company earns $100,000 a month from ten customers. Its largest customer supplies $40,000. Serving that customer creates $30,000 in directly attributable costs. The other customers supply $60,000 and create $30,000 in those costs.

The largest customer represents 40 percent of revenue but $10,000 of the $40,000 contribution before shared costs. That is 25 percent of contribution. Neither percentage is the customer’s final profit. Shared staff, rent and other costs still need an account.

The difference matters if the owner uses revenue alone to evaluate a price request. A small discount on a large account can consume a meaningful part of what that account leaves. A rate increase can also make sense on paper and cost more if the customer leaves and the dedicated team remains.

What can stop when the work stops?

For a separate cash comparison, assume the month’s stated revenues are collected and its stated service costs paid within that month. Suppose $20,000 of the large customer’s monthly service costs would stop quickly if its work ended. The remaining $10,000 supports people and equipment the company has already committed to. Losing the account removes $40,000 of receipts and only $20,000 of immediate payments. The near-term cash deterioration is $20,000, not the account’s previous $10,000 contribution. Whether that creates a cash shortfall also depends on the opening balance and the company’s other payments.

Those are invented assumptions, but they expose a practical distinction. The cost of serving a relationship and the cost that disappears when it ends need not be the same. Put a date against changes in payroll, premises and equipment use. Avoid counting a saving before it can occur.

Chapter 6’s turnaround makes that mismatch visible: a business can shrink while commitments from its larger form remain. Chapter 9 adds another dependency when the person paying the operator relies on receipts from customers further along the chain. Concentration can live in a distributor as well as in the final buyer.

A good relationship can still need a second route

Longstanding customers often deserve thoughtful service and terms. Understanding dependence does not require treating them with suspicion. It requires knowing how the company would respond to a change that neither side wants.

Ask whether the customer occupies a fixed day, needs specialist equipment or depends on one employee’s knowledge. Consider whether a new buyer could use that capacity. A full schedule is less reassuring when every opening must be sold to the same person.

A second sales route may cost more than serving the established customer. Chapter 9 treats a distributor’s reach as something the operator would otherwise have to build. Compare the realistic cost and time of developing alternatives. “We could replace the customer” is not an operating plan until there is a credible route from available capacity to paid work.

Keep the review short enough to revisit. Record the revenue share, contribution assumptions, payment history, dedicated commitments and the next date on which the exposure changes. Then choose the appropriate action: retain the relationship on sound terms, renegotiate a costly part, develop another source of demand or stop adding capacity that only one buyer can support.