Agencies get laser-focused on boosting LTV, while the fundamentals of cash flow get overlooked. And here’s the issue – LTV is a time-based metric. You don’t earn it overnight.
What you should be aiming for is LTV growth inside 90 days. After that point, the financial strain kicks in – and if CAC isn’t paid back within that window, the backend starts to crack.
Let’s break it down.
Imagine you’ve doubled LTV in a year. Sounds like a win, right? But if your CAC isn’t paid back within 180 days, your acquisition engine stalls. You’re constantly front-loading cash for new cohorts without getting enough return soon enough to reinvest. Cash conversion slows down, and that puts real pressure on your ability to scale.
The truth? CAC payback over 90 days can kill momentum – no matter how promising your LTV looks long-term.
And here’s what most people get wrong: improving CAC payback isn’t just about increasing AOV. It’s often about reducing CAC itself – which comes down to rigorous testing and optimisation.
You need to clearly understand three key relationships:
1. LTV vs CAC – and how that links to AOV and conversion rate
It’s not just what a customer is worth. It’s how quickly they become profitable, and how your site and funnel support that.
2. Contribution margin vs CAC – and the impact of each incremental pound
If margin doesn’t scale with spend, you’re fuelling growth at a loss.
3. Cash conversion cycle – and how long it takes to get your money back
This is the heartbeat of a healthy DTC business. The longer the payback period, the slower you can grow.
The brands that scale efficiently know this inside out. They prioritise fast payback, protect cash flow, and build LTV in the background – not the other way around.
If you’re spending on paid media, this mindset shift is essential.
Post inspired by: Valentin Kuznetcov