If you lead revenue at a growing B2B company, the short answer is this: use a funnel to see where prospects drop off, use growth loops to make growth compound, and use HubSpot's Loop Marketing to run those loops as one system. How much of each your business needs depends on your growth stage.
This article is for CEOs, founders, CROs and revenue leaders who are choosing a growth model. You will get a fair comparison of the three, a side-by-side table, decision rules for early, scaling and mature companies, and a way to run a funnel view for reporting alongside a loop for operating.
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Growth Loops Growth loops are closed systems where each round's output, such as new users, data or revenue, is reinvested as the input of the next round. |
The funnel is the model most B2B teams already use. Effort and ad spend go in at the top, awareness builds, prospects move through consideration and purchase, and customers come out at the bottom. It is a one-direction picture of the customer journey, which is why it still works so well as a reporting tool.
What the funnel does well is visibility. You can see where conversions fall off, which channels deliver and how the handoff between marketing and sales performs. Pipeline stages, forecasts and channel reports are natural outputs of the funnel model.
Its limit is that it stops at the purchase. Retention, expansion and advocacy sit outside the picture, so each new customer looks like a finished job instead of the start of the next round.
Measurement is also a struggle for many marketers. In HubSpot's 2026 State of Marketing survey, measuring the ROI of marketing activities was the top challenge, named by 33% of respondents.
A funnel covers everyone from first awareness to purchase, including people who may never buy. A pipeline tracks only the deals you have opened, stage by stage, each with a value and an owner. Most teams report on both: the funnel for demand and the pipeline for forecasting.
Growth loops are closed-loop business systems that reinvest outputs to drive growth. Reforge's 2018 essay, Growth Loops are the New Funnels, by Brian Balfour, Casey Winters, Kevin Kwok and Andrew Chen, describes them as systems where inputs pass through a process that produces more of an output, which you then reinvest in the input.
The essay contrasts this with funnels, which run in one direction and offer no way to reinvest what comes out at the bottom. The power of a loop is that reinvestment: each round's output pays for the next one.
Each loop works like a closed chain reaction. The actions of current users give new users a reason to arrive. A customer shares a report with a colleague, the colleague signs up, and that user shares the next report. The output of round one becomes the input of round two.
Four types come up most often:
A well-designed loop can combine mechanisms, such as referrals and content sharing. Before you build any of them, diagnose how your current system works. Loops sit on top of real behavior, so mapping where customers come from and what they do after they buy comes first.
Ownership sits with cross-functional growth or GTM teams. Product, marketing, sales and customer success all play a part, because a loop cuts across the customer journey instead of living inside one department.
Loop Marketing is HubSpot's framework. HubSpot describes it as "a four-stage framework any marketing team can use to grow in the AI era". For the full picture, see our guide to what Loop Marketing is. Here is the short version, based on HubSpot's own description of the stages.
HubSpot also asks you to build a Taste Profile first, so AI has the context to match your brand's voice. Personalization is the reason the Tailor stage matters. In HubSpot's 2026 State of Marketing survey, 93.2% of marketers said personalized or segmented experiences have led to more leads and purchases.
In practice, the framework asks marketing, sales and customer experience to work from the same feedback. Each stage is detailed in the four-stage Loop Marketing playbook with the metric for each. The cycle does not end when a visitor converts, and each pass gives the next one better data. Where a single growth loop handles one compounding motion, Loop Marketing is the operating routine that keeps several of them learning.
The flywheel came first. In How the Flywheel Killed HubSpot's Funnel, HubSpot explains why it moved on: funnels produce customers but do not consider how those customers can help you grow, and the momentum built while winning a customer is lost once the deal closes.
The flywheel has three phases. Attract earns attention with useful content. Engage makes it easier to buy on the buyer's own timeline. Delight helps customers reach their goals. The energy comes from happy customers, whose referrals and repeat purchases push the next turn.
The flywheel model made customer experience the center of growth. Growth loops make that idea precise by naming the trigger, input and output of each turn. A useful shorthand: the flywheel is the philosophy, growth loops are the mechanics and Loop Marketing is the operating routine.
Each model answers a different question. The funnel asks where prospects drop off. A growth loop asks which output can feed the next input. Loop Marketing asks how you run the whole thing as a system that keeps learning.
| Criterion | Funnel | Growth loop | HubSpot Loop Marketing |
|---|---|---|---|
| Question it answers | Where do prospects drop off? | Which output feeds the next input? | How do we keep learning and improving across channels? |
| What it gives you | Conversion visibility, forecasts, channel reports | A compounding mechanism you can design and measure | An operating routine built on four stages |
| Who owns it | Marketing and sales leaders, RevOps | Cross-functional growth or GTM teams | Marketing, sales and customer success leaders together |
| Setup effort | Light: stages and reports | Moderate: loop design and a few cycles of data | Heavier: connected data, automation and a review rhythm |
| Where it ends | At the purchase | Wherever you stop reinvesting | It keeps cycling after conversion |
| How it treats customers | As prospects moving through stages | As participants whose actions feed the next round | As people whose preferences shape the next message |
| Best fit | Early stage | Scaling stage | Mature stage |
| Role of AI and data | Measures what already happened | Feeds on usage and content signals | Uses AI to tailor content and adapt it |
The right model depends on how complex your go-to-market is, not only on revenue. To judge where your own system stands, take the marketing maturity self-check before choosing. A company with one product, one segment and founder-led sales faces a different problem from one running several motions across regions. These are the decision rules, stage by stage.
You have a small team, one main product, a few channels and perhaps founder-led sales. Your focus is understanding who finds value, how they find you and how many convert. A simple funnel view gives you that visibility and shows where the journey breaks.
You can still map one basic loop, such as a referral or content loop. Choose it by looking at how your users already behave. Full Loop Marketing may be too heavy now, but Express still applies: get your brand, positioning, strategy and messaging clear from day one.
You now have dedicated sales and marketing teams, more than one segment and many touchpoints. This is where the funnel model starts to leak. Handoffs between teams cost momentum, and retention and expansion signals get lost.
Growth loops become practical here. Design a referral, content or product-usage loop that connects acquisition, activation and retention. Introduce Loop Marketing to bring teams around shared data, campaigns and feedback, so insights from one loop reach the others.
You manage several products, regions and partner channels, plus a customer success team. You need acquisition, product-led, sales-led and advocacy loops running together. Loop Marketing in HubSpot can serve as the shared routine that sends insights back into every stage.
Funnels stay underneath for reporting on specific motions, such as enterprise sales. They stop being the strategy and become one of the views you use to check it. The move is a gradual evolution, not a switch.
Funnels and loops are not rivals. You can use a funnel to measure conversion and forecast revenue while using growth loops to design how demand actually gets created. Both views run at the same time on the same data.
For example, you track lead to opportunity to closed deal for the forecast. Meanwhile a product adoption loop runs: trial activation prompts sharing, sharing brings in new users, and those users feed the pipeline.
The funnel tells you where things are working. The loop tells you what to build so that more of it happens.
This is the shift described in our post on the evolution from funnels to connected systems: from isolated tactics to one connected architecture. Reporting and operating then stop competing for the same budget.
Do these in order, and keep the first loop small.
Build the model in two passes. First map the loop in plain words: its steps, and what each step outputs. Then put numbers on each step so you can forecast what a round produces and see which absolute figures, such as sign-ups per round, are worth improving first.
Connected data decides how far this goes. Salesforce's 2025 MuleSoft Connectivity Benchmark found that the average enterprise manages 897 applications and only 29% are integrated. A loop needs its steps to share records, or the output never reaches the input.
Loops are cross-functional by nature, so incentives and workflows shift across your teams. Here is what each one gets.
Sales starts watching signals such as product usage, referral events and expansion triggers, which say more about intent than a basic lead score. Those signals only help if the records behind them are right.
Salesforce's 2024 State of Sales research found that only 35% of sales professionals completely trust the accuracy of their organization's data. A shared loop gives sales clearer feedback to marketing and a firmer basis for prioritizing accounts.
Marketers move from running one-off campaigns to maintaining systems that reuse assets and data. The metrics change. Alongside channel results, you track how often a loop starts, how often it completes, how fast it turns and what it contributes to revenue.
Shared lifecycle stages also give marketing a common language with sales and customer success, which makes alignment easier to see in the numbers.
Customer success shifts from reactive service to owning loops for retention, expansion and advocacy. Health data can trigger education, renewal and referral flows, and each satisfied client becomes a source of the next introduction.
What customer success hears also shapes marketing messages and sales qualification. When it feeds back which outcomes clients value, the whole system understands the customer better, and long term loyalty becomes something you design for instead of hope for.
Ask one question: is your main problem seeing where revenue leaks, or making growth compound? If it is the first, tighten your funnel. If it is the second, design one growth loop around an action your customers already take, and test it.
Keep the funnel for reporting. When your first loop runs and you can see it compounding, begin formalizing Loop Marketing in HubSpot to connect your loops into one operating model. That is how a business gets long term growth from the work it has already done.
Propello designs and builds connected GTM systems on HubSpot. If you want help choosing and building the right mix for your stage, an audit is the place to start.