The A-CAR Marketplace Framework
A practical framework for building marketplaces that actually scale
Most marketplace failures don’t come from bad ideas. They come from working on the wrong thing at the wrong time.
Founders ship features, redesign onboarding, add growth loops, or chase retention—without understanding where the marketplace is actually breaking.
The A-CAR Marketplace Framework exists to prevent that.
A-CAR helps founders identify the single constraint holding their marketplace back, so effort is spent where it creates real leverage.
What is A-CAR?
A-CAR breaks the marketplace journey into four sequential stages:
Attract
Can you reliably bring the right supply and demand into the marketplace?
Convert
Do users trust the platform enough to complete a transaction?
Adopt
Do users experience value quickly and return on their own?
Retain
Does the marketplace get stronger as usage compounds?
Each stage depends on the one before it.
- You cannot retain users who never adopt.
- You cannot adopt without conversion.
- You cannot convert users you cannot attract.
Why sequencing matters in marketplaces
Traditional product frameworks assume linear user funnels. Marketplaces are systems, not funnels.
They have:
- • Two (or more) user types
- • Asymmetric incentives
- • Cold-start dynamics
- • Liquidity constraints
- • Trust and timing dependencies
Because of this, optimizing the wrong stage creates negative ROI.
Examples:
- • Improving retention when users never experience value
- • Scaling acquisition before conversion works
- • Adding features when liquidity is the real problem
A-CAR forces founders to answer one question first:
"Where is the system actually breaking right now?"
The four A-CAR stages explained
Attract
Can the marketplace bring in the right users?
This is about quality and balance, not raw traffic.
Typical Attract problems:
- • Supply signs up but never activates
- • Demand shows interest but can’t find matches
- • Manual acquisition doesn’t scale
- • One side grows faster than the other
Common Attract signals:
- • Low qualified sign-ups
- • Poor geographic or category coverage
- • High acquisition cost with low downstream value
Convert
Do users trust the marketplace enough to transact?
Conversion is where marketplaces often stall.
Typical Convert problems:
- • Users browse but don’t commit
- • Trust signals are weak or unclear
- • Pricing or fees create hesitation
- • The transaction flow feels risky or confusing
Common Convert signals:
- • Low booking or purchase rate
- • High drop-off at checkout or messaging
- • Heavy pre-transaction support required
Adopt
Do users experience value quickly and repeatedly?
Adoption is about time-to-value.
Typical Adopt problems:
- • Users transact once and disappear
- • Value is delayed or unclear
- • The first success feels accidental
- • Users need constant nudging to return
Common Adopt signals:
- • Long time to first transaction
- • Low repeat usage
- • Heavy operational intervention required
Retain
Does the marketplace compound over time?
Retention is where network effects emerge—but only after the earlier stages work.
Typical Retain problems:
- • Users churn despite successful usage
- • Supply multi-homes aggressively
- • Demand treats the marketplace as a one-off tool
Common Retain signals:
- • Declining cohort usage
- • Low lifetime value
- • Weak referral or organic growth
The most important rule of A-CAR
"There is always one primary constraint."
Founders often want to fix everything at once. That’s how roadmaps turn into feature factories. A-CAR is intentionally restrictive: One primary stage, clear deprioritization of everything else. This is how leverage is created.
How A-CAR is used in Marketplace Roadmap
Inside Marketplace Roadmap, A-CAR is not shown as a framework or acronym. Instead, it powers:
Founders experience A-CAR as guided clarity, not theory. The framework operates in the background to prevent premature optimization, reduce roadmap noise, and anchor decisions to real constraints.
A-CAR vs the "Feature Factory" trap
Many product teams fall into what’s often called The Build Trap—shipping more without learning more. In marketplaces, this becomes a Feature Factory:
- • Features added without impact
- • Bets made without evidence
- • Velocity without direction
A-CAR exists to stop that pattern. Every initiative must answer:
- • What stage does this support?
- • What behavior should change?
- • How quickly should value appear?
- • What evidence suggests this will work?
Who A-CAR is designed for
- First-time marketplace founders
- Non-technical founders
- Post-MVP teams seeking traction
- Studios and consultants guiding strategy
Final takeaway
Marketplaces don’t fail because founders don’t work hard enough. They fail because effort is misaligned.
The A-CAR Marketplace Framework ensures you are working on the right problem, at the right time, for the right reason.