Rule-based AI vs machine learning: How we choose the right approach for clients

Date
September 8, 2025
Hot topics 🔥
AI & Tech
Contributor
Mario Grunitz
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Rule-based AI vs machine learning: How we choose the right approach for clients

Key takeaways

  • Contrasting Approaches: Rule-based AI operates on predefined rules, while machine learning evolves its rules from data analysis.
  • Rule-based AI: Ideal for deterministic tasks with clear, straightforward rules and limited data.
  • Machine Learning: Suited for complex tasks requiring adaptability and large datasets for pattern recognition.
  • Application Fit: Rule-based systems excel in precision-oriented tasks, machine learning thrives in predictive analytics and dynamic environments.
  • Hybrid Systems: Combining both approaches offers versatile solutions, balancing precision with adaptability, and represents the future of enterprise AI.
  • Strategic Choice: The decision between rule-based AI and machine learning depends on specific project requirements, data availability, and business objectives.

The strategic decision

Over 20 years in technology, I’ve seen AI evolve from experimental systems to business-critical infrastructure. Today, one of the most important strategic decisions we help clients navigate is choosing between rule-based AI and machine learning, or increasingly, how to combine both approaches effectively.

The stakes are higher than ever. 90% of enterprise apps are expected to use AI by 2025, which means businesses can’t afford to guess. The wrong approach wastes resources, the right one transforms operations. From our experience implementing AI solutions across industries, I’ve learned that understanding the fundamental differences between these approaches is essential for making informed decisions.

With AI commoditisation shaping our digital landscape, it’s crucial to understand both the strengths and weaknesses of these technologies to identify the right solution for your business.

If you’re looking for interesting approaches to understanding more about artificial intelligence, here are some of our best AI books to provide a holistic understanding of the technology.

Two approaches, different strengths

From our experience implementing AI solutions, we typically work with one of two contrasting approaches to obtain conclusions from data: rule-based and machine learning. Increasingly, however, we’re combining both to deliver maximum value. What’s particularly interesting in 2026 is how the landscape has shifted, 23% of organisations are now scaling agentic AI systems, which represents a new evolution of these foundational approaches.

What is rule-based AI?

A system designed to achieve artificial intelligence (AI) via a model solely based on predetermined rules is known as a rule-based AI system. We use rule-based systems when we need deterministic outcomes. They operate on straightforward cause-and-effect logic, which makes them perfect for scenarios where precision and consistency matter more than adaptability.

The makeup of this system comprises a set of human-coded rules that result in pre-defined outcomes. These AI models are defined by ‘if-then’ coding statements (i.e. if X performs Y, then Z is the result). Two important elements are “a set of rules” and “a set of facts,” and by using these, we can create a reliable artificial intelligence model. These systems can be viewed as an advanced form of robotic process automation (RPA).

Rule-based systems are immutably structured and unscalable, therefore they can only perform the tasks and functions they’ve been programmed for. Due to this deterministic nature, they only require very basic data and information to operate successfully.

In a recent insurance claims project we implemented, we used a rule-based system to validate claims data. By applying consistent validation rules, we reduced processing errors by 40% and cut approval time in half. The system checked for completeness, flagged inconsistencies, and ensured regulatory compliance automatically, exactly the kind of task where rule-based AI excels.

Current market analysis reveals that the rule-based segment continues to capture significant market share as it performs repetitive tasks efficiently across industries. Manufacturing leads RPA adoption due to its focus on optimising production processes. From my strategic perspective, rule-based systems remain essential when you need information quickly and errors cannot be tolerated, such as in medical diagnosis, finance processing, and compliance checking. Many AI music production tools utilise this type of system.

What is machine learning AI?

A system designed to achieve AI utilising the power of machine learning (ML) is known as a machine learning model. We turn to ML systems when we need to identify patterns in large datasets or predict outcomes without knowing exactly how to do so upfront. Machine learning systems define their own set of rules based on data outputs they have access to, without constant human intervention.

By taking outputs from data or experts, ML systems utilise a probabilistic approach, one that accounts for variations and probabilities to create informed results. This means they constantly evolve, develop, and adapt when new information is added, particularly when a human is in the loop. Find out more about what HITL means in a previous deep-dive blog.

The machine learning landscape has expanded dramatically. The MLaaS market reached USD 45.76 billion in 2025 and is projected to grow to USD 209.63 billion by 2030. This explosive growth reflects how essential ML has become for addressing challenges that rule-based systems struggle with, such as practical training of large datasets.

ML systems are mutable and nimble, allowing them to transform data and extract value through adaptive algorithms. The more data you feed the system, the more accurate it becomes in identifying patterns. What I find particularly exciting is how ML is evolving into agentic AI systems, autonomous entities capable of planning and executing multi-step tasks, which represents the next frontier in this technology.

Choosing the right approach

Based on the prerequisites and functionalities of rule-based AI and ML systems, which approach works best? As in all cases, it depends on your project requirements. Here’s how we typically guide clients through this decision:

Decision comparison

AspectRule-Based AIMachine Learning AI
Best forSmall data, straightforward rulesLarge datasets, complex patterns
FlexibilityFixed within parametersAdapts continuously
SpeedVery fast resultsDepends on training time
Use casesFault analysis, email routing, validationPredictive analytics, recommendations, forecasting
AccuracyPedantic and thoroughImproves with more data
SetupQuick implementationRequires extensive training
MaintenanceRule updates manualSelf-improving with new data
ExplainabilityTransparent logicOften “black box”

When we recommend rule-based systems

We typically recommend rule-based systems for projects that require small amounts of data and simple, straightforward rules. Think of this as a fit-for-purpose system, highly effective within its predetermined parameters, and limited outside of them. Rule-based systems are excellent for repetitive processes that require little-to-no human decision-making, such as fault analysis, email routing using triggers, and basic searching.

Rule-based systems deliver information quickly, as the limited parameters allow for speedy results. They’re also incredibly thorough, which is why we often use them in processes where errors cannot be tolerated, such as medical diagnosis and finance processing.

When we recommend machine learning systems

We turn to ML systems when large volumes of relevant data records are available for making accurate predictions. For processes with multiple factors, numerous potential outcomes, and dynamic variables, ML systems are the better choice.

ML systems work well when you need to predict an outcome but don’t necessarily know the exact path to get there. We’ve implemented ML for sales lead qualification, customer support automated responses, and situations with multi-variables. ML systems are best suited to rapidly changing environments like e-commerce recommendations, virtual influencers, and general forecasting.

In a recent e-commerce project, we implemented ML-powered product recommendations that analysed browsing behaviour, purchase history, and seasonal trends. The system increased conversion rates by 18% and average order value by 12%. YouTube and Netflix auto-suggestions are classic examples, the algorithms learn from your activity and continuously assess your preferences to suggest content based on evolving patterns.

Best of both: The hybrid approach

There are systems that combine rule-based AI with ML in what we call a hybrid approach. We’re increasingly implementing these hybrid solutions, and from our experience, they represent the future of enterprise AI.

By combining the two approaches, businesses can address the shortfalls of each system, providing a thorough solution that is both accurate and robust. This comes in the form of rule-based machine learning systems that identify and adapt their own set of rules. The defining characteristic is their ability to utilise relational rules that collectively represent the knowledge captured by the system, relying on knowledge bases rather than requiring constant human intervention.

What’s particularly relevant in 2025 and 2026 is how hybrid approaches have become standard practice. Organisations applying hyperautomation achieved 42% faster process execution and up to 25% productivity gains, according to UiPath’s Automation Trends Report 2025. Gartner predicts that 40% of enterprise applications will feature task-specific AI agents by 2026, up from less than 5% in 2025.

The rise of Generative AI has further solidified the need for hybrid approaches. GenAI models excel at content creation and complex reasoning, but they require rule-based guardrails to ensure brand guidelines, legal disclaimers, and compliance requirements are met. This dynamic illustrates that even cutting-edge AI relies on foundational, rule-based logic for safety and compliance.

Cloud adoption trends support this hybrid evolution. More than 70% of businesses are expected to employ industrial cloud platforms by 2027 to expedite business objectives, up from less than 15% in 2023. This shift enables organisations to implement sophisticated AI approaches that leverage both rule-based precision and ML adaptability.

In a logistics automation project we implemented, we combined rule-based routing protocols with ML-powered demand prediction. The rule-based system ensured compliance with delivery regulations and optimised routes based on known constraints, while the ML component predicted demand spikes and adjusted inventory allocation dynamically. The result was 30% faster delivery times with full regulatory compliance.

Quick reference: When to use what

Decision framework from our experience:

Choose rule-based when:

✓ Rules are clear and unchanging

✓ Speed and precision are critical

✓ Limited data available

✓ Compliance requires explainability

Choose machine learning when:

✓ Patterns are complex or hidden

✓ Large datasets available

✓ Adaptability to change needed

✓ Predictive capability required

Choose hybrid when:

✓ Need both precision AND adaptability

✓ Compliance requires guardrails on ML

✓ Scaling across complex workflows

Strategic implications for 2026

From our strategic perspective, both rule-based systems and ML systems have associated strengths and weaknesses, but these can only be determined by your specific project requirements and business objectives.

If you need precision within a relatively small framework parameter, rule-based systems are your answer. If you have access to large amounts of data and need to predict outcomes or identify hidden patterns, ML systems are the better choice. If you have business needs that require both precision and large data processing for predictions and forecasting, then a hybrid approach is what you’re after.

What I’ve observed over the past two years is that the most successful AI implementations are hybrid. With 90% of enterprise apps expected to use AI by 2025, businesses that understand when to apply each approach, and how to combine them effectively, will gain significant competitive advantage.

The key is matching the approach to your strategic objectives. Don’t choose technology based on trends, choose based on what your business actually needs to accomplish. Start with your desired outcomes, then work backwards to determine whether rule-based precision, ML adaptability, or a hybrid combination will get you there most effectively.

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Mario Grunitz

Mario is a Strategy Lead and Co-founder of WeAreBrain, bringing over 20 years of rich and diverse experience in the technology sector. His passion for creating meaningful change through technology has positioned him as a thought leader and trusted advisor in the tech community, pushing the boundaries of digital innovation and shaping the future of AI.
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