Customer value and lifetime value: what a customer is worth, and what loyalty really buys

Every marketing plan makes an assumption about customers: how much they are worth, how long they stay and what keeps them. This piece makes those assumptions explicit.

• Customer value is what a customer gets from an offer relative to what it costs them, compared with the alternatives. Kotler, Keller and Chernev treat a clear value proposition and positioning as the route to high customer value and satisfaction, and so to repeat purchase^1, 2.
• Customer lifetime value (CLV) is the expected sum of the discounted future margins a customer brings; Gupta, Lehmann and Stuart showed that adding it up across customers can value a whole firm³.
• Retention economics became famous through Reichheld and Sasser's 1990 Harvard Business Review article⁵, but the best-known figure from it is contested⁷.
• The Net Promoter Score (NPS), introduced by Reichheld in 2003⁹, is widely used; independent tests did not replicate the claim that it predicts growth better than other measures¹³.

The decision it informs: how much to spend to win and keep each kind of customer, and which numbers the board should see. Read it with the CRM and loyalty primer and the glossary entries for LTV and CAC.

The 16th edition of Marketing Management (Pearson, 2021) sets this out under "designing value", with a chapter on crafting a customer value proposition and positioning¹. Its logic is simple: a clear value proposition and positioning help deliver high customer value and satisfaction, which lead to high repeat purchases².

Two practical points follow for a communications team:

• Value is judged against alternatives A customer compares benefits (functional, emotional, social) with costs (price, time, effort, risk) and with what competitors offer. Communication can make benefits visible and lower perceived risk; it cannot replace them.
• Satisfaction is promise against delivery Over-claiming raises expectations that the experience then misses. The message house should promise what operations can deliver.

Sunil Gupta, Donald Lehmann and Jennifer Ames Stuart's "Valuing Customers", published in the Journal of Marketing Research in 2004, defined the value of a customer as the expected sum of discounted future earnings, based on assumptions about retention and profit margin; the value of all customers then depends on how many are acquired and what acquiring them costs³. Their point was that valuing customers makes it feasible to value firms, including fast-growing firms with negative earnings³. The paper won the William F. O'Dell Award in 2009⁴.

With a constant margin m per year, a constant retention rate r and a discount rate i, the discounted margins expected after the first year add up to m × r / (1 + i − r). It is a simplification (margins and retention change over a customer's life), but it shows which levers matter.

Illustrative example. A subscription business earns a margin of 100 a year per customer, keeps 80% of customers each year and discounts at 10%. The formula gives 100 × 0.8 / 0.3, about 267. If retention rises to 85%, the same formula gives 85 / 0.25, or 340. If it costs 150 to acquire a customer, the ratio of lifetime value to acquisition cost moves from about 1.8 to about 2.3. These figures are invented for the arithmetic only; use the LTV to CAC calculator with your own.

In "Zero Defections: Quality Comes to Services" (Harvard Business Review, September–October 1990), Frederick Reichheld and W. Earl Sasser argued that service companies should borrow the manufacturing idea of zero defects and aim to keep every customer they can profitably serve⁵. The article's best-known line, as Bain summarises it, is that companies can boost profits by almost 100% by retaining just 5% more of their customers⁶.

That figure needs care. The Ehrenberg-Bass Institute argues that the article does not show empirically that lower defection causes large profit increases, and that its reasoning is a thought experiment⁷. The safer lesson is the mechanism, not the number: when margins rise with tenure and acquisition is costly, small improvements in retention compound. Test it on your own data.

Byron Sharp and the Ehrenberg-Bass Institute add a structural limit. Double jeopardy means that loyalty is largely a predictable function of market share: brands differ greatly in how many customers they have and much less in how loyal those customers are⁸. Trying to grow by focusing only on loyalty does not work; a brand must increase its penetration⁸.

The two views are less opposed than they sound. Reichheld and Sasser wrote about service businesses where each customer's defection is visible and costly⁵; Sharp writes about markets where most buyers buy several brands^7, 8. In both, the plan needs to win new buyers and keep the ones it has; the debate is about the balance, and the evidence says not to put all the weight on loyalty. See the retention and loyalty and customer acquisition hubs.

Reichheld, a Bain Fellow and founder of Bain's loyalty practice¹², introduced the Net Promoter Score in "The One Number You Need to Grow" in the Harvard Business Review in December 2003⁹. Bain's history of the metric says Reichheld's team tested several questions against customer behaviour, and that one worked best for most mature, competitive industries: "How likely are you to recommend Company X to a friend or colleague?"¹⁰. Respondents who answer 9 or 10 are promoters¹¹; the score is the percentage of promoters minus the percentage of detractors, the low scorers⁹, so it runs from −100 to +100.

The critics tested the claim directly. Timothy Keiningham, Bruce Cooil, Tor Wallin Andreassen and Lerzan Aksoy, in the Journal of Marketing in 2007, used longitudinal data on 21 firms and more than 15,500 interviews from the Norwegian Customer Satisfaction Barometer and could not replicate the "clear superiority" of Net Promoter over other measures in the industries Reichheld had cited¹³. The paper won the Marketing Science Institute/H. Paul Root Award¹⁴. Jeff Sauro of MeasuringU, replicating the original analysis, observed that it correlated NPS with past growth, which supports concurrent validity but not prediction¹⁵.

The fair use: NPS is a cheap, understandable signal of how customers feel, and the follow-up question is often the most useful part. It is not proven to be the one number that predicts growth^13, 15; read it with retention, repeat purchase and revenue per customer. See NPS.

• Segment by value, not only by demographics Lifetime value differs by segment; acquisition budgets and messages should too. See segmentation and RFM.
• Write the retention journey Onboarding, first use, renewal and win-back each need a message and an owner; CRM, email and service carry most of it.
• Keep acquisition alive Double jeopardy means most growth still comes from new buyers⁸; do not let the retention plan starve the brand plan.
• Make referral easy Promoters only add value if they actually recommend; see advocacy and referral.
• Report the economics Lifetime value, acquisition cost, churn and retention rate belong on the same page as brand and campaign measures.

1. Quoting "5% more customers kept, almost double the profit" as a law It came from the authors' arithmetic, and it is contested^6, 7.
2. Computing one lifetime value for all customers The average hides the segments that make or lose money.
3. Using revenue instead of margin A customer who buys a lot at a loss is not valuable.
4. Treating NPS as proof of growth The independent evidence does not support it¹³.
5. Building loyalty schemes for customers who would stay anyway Measure the incremental effect before scaling one.

Illustrative example. A software company sees acquisition costs rising. Its team computes lifetime value for three segments, finds that small accounts barely repay their acquisition cost while mid-sized accounts repay it several times, and shifts acquisition spend and messages towards mid-sized firms. It adds an onboarding sequence for the first 90 days, asks the NPS question after onboarding with a follow-up "why?", and reviews the verbatims monthly with product and service.

Your checklist for Monday:

1. Write the value proposition for your main segment in one sentence, against the alternative customers actually use.
2. Estimate margin, retention and acquisition cost per segment; run them through the LTV to CAC calculator.
3. Map the retention journey (onboarding, first value, renewal, win-back) with an owner for each step.
4. Check penetration as well as retention, so the plan still recruits new buyers.
5. If you use NPS, add the "why?" question and route the answers to someone who can act.
6. Put lifetime value, acquisition cost and churn on the same dashboard as brand measures; see measuring effectiveness.

• Kotler, Keller and Chernev, Marketing Management, 16th edition (Pearson)¹.
• Gupta, Lehmann and Stuart, "Valuing Customers" (Journal of Marketing Research, 2004)³.
• Reichheld and Sasser, "Zero Defections" (HBR, 1990)⁵, and the Ehrenberg-Bass Institute's "Loyalty Myths"⁷.
• Reichheld, "The One Number You Need to Grow" (HBR, 2003)⁹, and Keiningham et al. (Journal of Marketing, 2007)¹³.
• On IMC Report: how brands grow, objectives and KPIs, and the CRM and loyalty hub.