Why traditional CRO methods need adapting for subscriptions

TLDR

Many CRO targets will inadvertently harm ongoing subscription performance, as they apply the wrong success metrics to recurring revenue models.

We explain which CRO metrics create problems for subscriptions, why immediate conversion metrics miss the bigger picture and highlight the extended testing methodology to actually drive sustainable subscription growth.

Full article

Your CRO project just delivered great news: their latest pricing test increased conversions by +23%. But six months later, your churn rate has climbed and customer lifetime value has dropped. 

Question: What went wrong?

Answer: you applied ecommerce optimisation methods to a subscription model.

They measured success using conversion rates instead of customer relationships, which works perfectly for one-time purchases but can create challenges for recurring revenue models.

This is an increasingly common issue as more businesses adopt subscription models without adjusting their optimisation approach accordingly.

The core challenge: misaligned success metrics

Traditional CRO measures success with immediate metrics: conversion rates, cart completion, revenue per visitor. These work brilliantly for selling products because the customer relationship ends soon after the purchase.

But Subscription businesses operate differently.

They begin relationships at purchase, where every conversion starts a long term relationship that can either generate significant value or become a costly acquisition mistake.

When traditional CRO methods are applied to subscription checkout flows using ecommerce metrics, they often optimise for customers who convert well but retain poorly. The unintended result = the wrong customer profile.

Traditional A/B Tests That Don’t Work for Subscription Businesses

1. Friction removal

Traditional approach: Removed form fields, simplified checkout, barriers to conversion are eliminated. 

The problem it causes: Customers buying via minimal friction often don't fully consider the subscription commitment. They may experience buyer's remorse and churn faster  than customers who thought through their purchase.

2. Urgency and scarcity

Traditional approach: "Limited time offer" or "Only 3 spots left" messaging drives immediate conversions.

The problem it causes: Customers converting under artificial pressure aren’t ready to commit to ongoing payments. They may cancel once the urgency passes and they have time to reconsider.

3. Discount depth

Traditional approach: Compare 20% vs 30% vs 50% off to find the highest converting discount.

The problem it causes: Deeper discounts will attract price-sensitive customers, but who will also churn when pricing normalises. In the subscriptions world, we call this “bill shock”. A deep discounting strategy simply optimises for customers who can’t/won’t sustain your regular pricing over the long-term.

4. Payment method optimisation

Traditional approach: Optimise for the payment methods with highest conversion rates. 

The problem it causes: Some payment methods convert well but will create billing issues later. For example, Shop Pay converts excellently but currently has renewal processing bugs that increase failed payments down the line.

5. Social proof

Traditional approach: "Join 10,000+ customers" messaging to increase conversion confidence.

The problem it causes: Social proof based on customer volume can attract followers rather than committed users. Subscription businesses benefit more from customers who choose them for product value rather than popularity.

6. Checkout speed

Traditional approach: Reduce checkout to the minimum possible steps for maximum conversion.

The problem it causes: Very fast checkouts don't give customers time to understand subscription terms, billing schedules or commitment levels. This confusion leads to churn.

The unintended consequences of misaligned metrics

These testing approaches can inadvertently harm subscription businesses:

• Attracting the wrong customers: Tests that optimise immediate conversion will attract customers less prepared for a subscription.

• Misleading performance signals: High conversion rates mask declining customer quality, making it harder to identify underlying business issues.

• Operational strain: Customers who don't understand what they've signed up for, leading to higher customer support, payment processing issues, etc.

• Resource misallocation: Teams focus heavily on conversion optimisation instead of retention and customer success, potentially missing the activities that actually drive sustainable subscription growth.

Better A/B testing for subscriptions

Effective subscription A/B testing requires a different approach and evolved success metrics:

Immediate success criteria (0-7 days)

Measure conversion rates and conversion quality:

• Onboarding completion rates: What percentage of new customers complete the setup processes?

• Initial engagement metrics: How many subscribers use your core features in their first week?

• Payment method reliability: Which payment methods have lowest failure rates on subsequent charges?

• Support ticket volume: Which checkout variations cause more customer confusion?

1-month success criteria

Monitor early relationship health:

• Retention by cohort: What percentage of each test variation still subscribes after 30 days?

• Engagement consistency: How often are subscribers from each variation using your product?

• Feature adoption rates: Which tests lead to broader product usage?

• Customer satisfaction scores: How do new subscribers rate their early experience?

2-3 month success criteria

Measure relationship stability:

• Cohort retention curves: How do retention rates compare between test variations over time?

• Payment success rates: Which variations have better billing cycle completion?

• Upgrade behavior: Do certain checkout experiences lead to higher plan upgrades?

• Referral patterns: Which customers become advocates and refer others?

6-month success criteria

Evaluate long-term business impact:

• Customer lifetime value: What's the actual LTV difference between test variations?

• Churn reasons analysis: Why do customers from different variations cancel?

• Expansion revenue: Which test variations lead to higher spending over time?

• Net promoter scores: How do long-term satisfaction ratings compare?

How to structure subscription A/B tests

Here’s how to adjust your A/B testing for subscriptions:

1. Extend testing periods: Run tests for minimum 2-3 months to capture full retention cycles. Don't declare winners based just on immediate conversion data.

2. Cohort-based analysis: Track how specific groups of customers perform over time rather than looking at overall averages that mask important patterns.

3. Quality score development: Create composite metrics that balance conversion volume with leading indicators of subscriber success.

4. Segmented measurement: Different customer segments may respond differently to the same checkout experiences. Measure results by traffic source, customer type and intended usage.

5. Long-term tracking systems: Implement measurement systems that connect initial test experiences with months of subsequent customer behavior.

What success actually looks like

A successful subscription A/B test might show:

• 15% lower conversion rates

• 40% better 6-month retention

• 60% higher customer lifetime value

• 25% fewer support tickets per customer

Traditional CRO would call this test a failure based on conversion rates. Subscription businesses would call it a massive victory based on relationship quality.

The CRO challenge

Some agencies focussed purely on CRO face a genuine challenge when working with subscription businesses because:

• Their proven success metrics are designed for transaction models, not subscription models

• Their standard testing periods may be too short to capture relationship dynamics

• Their core expertise is in conversion optimisation rather than long-term relationship optimisation

• Their client reporting typically focuses on immediate, measurable results rather than extended value creation

This creates a gap where agencies may inadvertently optimise subscription businesses using methods that work brilliantly for product sales but can be counterproductive for recurring revenue models.

AND THIS IS WHY FILDI EXISTS.

What subscription-focused optimisation looks like

Subscription businesses need optimisation partners who understand recurring revenue dynamics: measuring success over months rather than days, optimising for customer relationships rather than just conversions and recognising that the highest-quality subscription customers often convert more thoughtfully but stay significantly longer.

The agencies that develop subscription-specific testing methodology will build stronger businesses for their clients and create sustainable competitive advantages that compound over time.

This represents a significant opportunity for CRO agencies ready to expand their expertise into the growing subscription economy.

Ready to audit your subscriptions business?

Get your FILDI Subscription Performance Audit now, identify exactly what's costing you money and get the roadmap to fix it.

What does a Subscriptions Audit entail? We conduct deep analysis across your subscription data to present a comprehensive performance picture. Our proven methodology examines customer lifetime value, acquisition costs, growth efficiency and retention patterns.

More importantly, you'll receive specific and actionable recommendations based on our findings. We don't just tell you what's broken, but we'll also prioritise what to fix now.

Our audit delivers immediate value: clear identification of your biggest revenue leaks, specific opportunities for growth and a strategic plan you can implement.