In 30 seconds
Mike Duboe discusses uncertain customer lifetimes, blended acquisition metrics and payback periods, while emphasizing customer psychology and creative work.
- 1Lifetime uncertaintyEarly customer lifetime estimates can be speculative.
- 2Hidden variationBlended ratios obscure channel and audience differences.
- 3PaybackPayback compares acquisition cost with subsequent gross margin.
- 4SegmentationMore granular estimates still depend on attribution and data quality.
- 5Tool, not strategyMetrics support strategy but do not replace customer understanding.
Takeaways
- Early customer lifetime estimates can be speculative.
- Blended ratios obscure channel and audience differences.
- Payback compares acquisition cost with subsequent gross margin.
- More granular estimates still depend on attribution and data quality.
- Metrics support strategy but do not replace customer understanding.
Read the edited text by chapter
Limits of LTV to CAC
Lifetime assumptions and blended averages.
In this 2023 conversation, investor and former growth leader Mike Duboe explains to Harry Stebbings why he is cautious about relying on a customer lifetime value to acquisition cost ratio. His remarks are business analysis, not investment advice.
First, young companies rarely know a customer’s true lifetime. Duboe asks how a two-year-old company can confidently assume a five-year customer lifetime without enough evidence.
Second, a blended ratio can hide differences between acquisition channels, search terms and audiences. Customers acquired through different routes may have very different economics.
Payback and strategy
Granular analysis and customer understanding.
Duboe prefers examining payback periods: how long gross margin from acquired customers takes to recover acquisition spending. He recommends matching paid acquisition costs to the relevant paid customers and improving granularity as data permits.
For example, search terms reflecting different purchasing intent can warrant different acquisition-cost thresholds. Segment-level estimates still depend on data quality, attribution and assumptions.
He recalls Bill Gurley’s warning that an LTV formula is a tool, not a strategy. A formula should not be used merely to justify ever larger marketing budgets.
Duboe adds that understanding customer psychology and producing effective creative work can matter more than mechanical optimization of a single metric.
More from this channel
1:00:17EN
20VC with Harry Stebbings· Oct 29, 2026Podcast · 3 speakersHarry Stebbings, Jason Lemkin and Rory O’Driscoll on AI financing and venture betsGuest Jason Lemkin, Rory O’Driscoll · Host Harry StebbingsThe investors debate AI lab economics, spending on infrastructure, open-model risks and how to evaluate fast-moving private investments.
23:48EN20VC with Harry Stebbings· Oct 26, 2026Podcast · 2 speakersSatya Nadella on Zero Trust for AI and Why Every Company Should Own Its IntelligenceGuest Satya Nadella · Host Harry StebbingsThe Microsoft CEO argues that capable agents need security boundaries even as alignment research remains unsettled, and explains why firms should retain the value created by their own AI use.
1:13:26EN20VC with Harry Stebbings· Oct 24, 2026Podcast · 2 speakersNaveen Rao on Energy, AI Hardware, Verification and the Future of RoboticsGuest Naveen Rao · Host Harry StebbingsThe Unconventional AI founder argues that energy efficiency will shape AI hardware, while the growing volume of model output makes verification more valuable.
59:41EN20VC with Harry Stebbings· Oct 22, 2026Podcast · 3 speakers20VC: Venture Fund Size, AI Valuations and the Changing Software MarketGuest Jason Lemkin, Rory O’Driscoll · Host Harry StebbingsHarry Stebbings, Jason Lemkin and Rory O'Driscoll debate venture concentration, infrastructure risk, code review and the assumptions behind fast-growing AI companies.
1:19:50EN20VC with Harry Stebbings· Oct 19, 2026Podcast · 2 speakersSameer Dholakia on AI Investing, Bessemer's Growth Strategy and Company CultureGuest Sameer Dholakia · Host Harry StebbingsThe Bessemer partner explains his approach to pricing fast-growing AI companies, backing founders and building teams, while discussing the risks behind his optimistic forecasts.
1:03:05EN20VC with Harry Stebbings· Oct 17, 2026Podcast · 2 speakersHarrison Chase on Building Reliable Agents, Model Routing and MemoryGuest Harrison Chase · Host Harry StebbingsThe LangChain co-founder explains why agents remain difficult to control, where domain expertise matters, and how his team manages coding-agent costs.