Choosing the Right Algorithm: Machine Learning vs. Heuristics

Miguel Carruego
9 min readFeb 15, 2024


Image created with DALL-E, obviously

In my journey as a product leader, one of the most interesting challenges I continually encounter is the strategic decision-making process involved in solving business problems with algorithms. Specifically, this often involves making a choice between leveraging traditional heuristics and embracing the increasingly popular machine learning models. The implications of this choice are profound, with the correct strategy having a considerable effect on the result, frequently defining the narrow margin between overwhelming success and clear-cut failure.

Heuristics, or simple business rules, have long been the cornerstone of problem-solving within many organizations. Their appeal lies in their simplicity and ease of implementation, coupled with a relatively low risk profile. In a business landscape that prized steady, predictable growth, heuristics were the go-to solution. However, in today’s fast-paced environment, where companies are under constant pressure to achieve unprecedented growth rates, the limitations of heuristics become strikingly obvious. The time it takes for these simple rules to yield the desired returns can be a critical bottleneck, hindering a company’s ability to compete effectively in its market.

On the flip side, machine learning projects, with their promise of automating decision-making and unlocking new insights from data, are increasingly viewed as a silver bullet by many in leadership positions. The allure of machine learning is undeniable, offering the potential to not only optimize existing processes but also to discover innovative approaches to longstanding challenges. Yet, the reality of implementing these projects is often fraught with complexity and high failure rates. A report by VentureBeat highlights a sobering statistic: 87% of machine learning projects ultimately fail. This figure underscores the considerable challenges involved, from data quality and availability issues to the technical expertise required to develop, deploy, and maintain machine learning models.

This article aims to navigate the nuanced landscape of machine learning versus heuristics, providing insights into the advantages and disadvantages of each approach. We will explore how businesses can make informed decisions that align with their strategic goals, operational capabilities, and the demands of an ever-evolving market landscape.

Understanding Heuristics

In my role as a product leader, the discussions I’ve had with engineers often revolved around strategic decisions that, on the surface, seemed to boil down to something as straightforward as implementing an “if statement.” While acknowledging this as a notable simplification, the essence of such discussions underscores a profound truth: the return on investment (ROI) for addressing a challenge with a basic business rule can be remarkably high. These hardcoded business rules are deeply rooted in past experiences and business acumen — attributes uniquely human, yet inherently susceptible to mistakes.

Heuristics, in their essence, are distilled wisdom from these experiences, translated into actionable rules. They embody a pragmatic approach to problem-solving, where the complexity of a full-scale machine learning project is eschewed in favor of simpler, more immediate solutions. However, the simplicity of heuristics belies their nuanced application and the strategic foresight required to implement them effectively.

Pros of Heuristics

  • Simplicity and Speed: Heuristics offer straightforward solutions that can be quickly implemented, providing immediate results. This rapid deployment cycle allows for agility in responding to business needs.
  • Low Resource Requirement: Unlike machine learning models that necessitate large datasets and significant computational power, heuristics operate with minimal resources. Their implementation requires neither extensive data nor complex algorithms, making them a cost-effective solution.
  • Flexibility: Heuristics can be easily tailored to address a wide range of problems without the need for substantial reprogramming. This adaptability makes them especially valuable in environments where business conditions and requirements frequently change.
  • High Interpretability: The transparent nature of heuristics makes them easy to understand and explain. This clarity is crucial for gaining stakeholder buy-in and for troubleshooting and refining business rules.

Cons of Heuristics

  • Inaccuracy: The simplicity of heuristics can be a double-edged sword. While they provide quick solutions, these may not always be the most accurate or optimal, especially in complex scenarios.
  • Bias and Assumptions: Heuristics are predicated on assumptions and experiences that may not universally apply. This reliance can introduce biases into the decision-making process, potentially skewing outcomes.
  • Scalability: As businesses grow and problems become more intricate, the limitations of heuristics become increasingly apparent. They may struggle to scale effectively, lacking the sophistication required to handle complex, multifaceted challenges.

A quintessential example of heuristics in action can be observed in the implementation of recommendation systems. In contrast with ML recommendation systems, a heuristic-based system deploys straightforward, rule-based logics to suggest products to customers, a method that is both cost-effective and rapid to implement. A common heuristic approach is the “people who bought X also bought Y” rule. This technique draws on the purchasing history of customers to identify patterns and recommend products that others have bought in conjunction with the item a customer is currently viewing or has added to their cart.

Understanding Machine Learning

Machine learning is a pivotal subset of artificial intelligence that equips systems with the ability to autonomously learn and enhance their performance over time, based on their experiences, without being explicitly programmed to perform specific tasks. This capability stands in contrast to traditional programming paradigms, where the logic and decision-making processes must be hard-coded for every conceivable scenario.

The fundamental principle behind machine learning is that algorithms can analyze data, learn from it, and then make decisions or predictions based on what they have learned. Learning in this context means identifying patterns in data and using these patterns to predict future data or to make decisions.

“The real problem is not whether machines think but whether men do.” — B.F. Skinner

Now, not everything is sunshine and rainbows. Implementing ML within an agile environment poses hard challenges due to the inherent differences in their methodologies. Agile focuses on flexibility, rapid iterations, and customer feedback, whereas ML involves complex, time-consuming development processes, relies heavily on large datasets, and outcomes can be unpredictable. Integrating ML with agile is further complicated by the need for specialized knowledge, making cross-functional collaboration difficult, and the complexities of deploying and maintaining ML models in production.

Despite these challenges, strategies such as modularizing ML development, leveraging MLOps for efficient deployment and maintenance, and fostering close collaboration between data scientists and agile teams can help bridge the gap. Successfully integrating ML into agile frameworks requires a careful blend of planning and flexibility to align the exploratory nature of ML with the swift, iterative demands of agile development.

Pros of Machine Learning

  • Data Adaptability: ML models excel in their ability to adapt to new data without being explicitly programmed for every possible scenario. This adaptability means they can handle complex datasets and evolve as they are fed more information, making them invaluable in dynamic environments where conditions and data patterns frequently change.
  • Accuracy: One of the standout advantages of ML is its potential for high accuracy in predictions and classifications, significantly surpassing traditional methods after adequate training. This high level of accuracy is crucial in applications where precision is paramount, such as in medical diagnoses, where machine learning models can analyze complex medical data to identify diseases with remarkable precision.
  • Automation: ML enables the automation of decision-making processes, significantly reducing the need for human intervention. This capability not only streamlines operations, making them more efficient but also can eliminate human biases from decisions. Automated systems powered by ML can handle tasks ranging from customer service inquiries with chatbots to managing inventory levels in supply chain management, freeing up human resources for more strategic tasks.

Cons of Machine Learning

  • Data Dependency: A significant limitation of ML is its reliance on large volumes of high-quality data for training. Gathering, cleaning, and preparing this data can be an extensive and expensive process. In cases where data is scarce, unrepresentative of the population, or of poor quality, the performance of ML models can be severely impacted, leading to inaccurate predictions or biased outcomes.
  • Complexity and Cost: The development and training of ML models, especially sophisticated ones like deep learning networks, involve a considerable investment of time and resources. This complexity not only extends to computational resources required for training and running these models but also encompasses the expertise needed to develop, deploy, and maintain them. For many organizations, the high cost and the need for specialized talent can be prohibitive, limiting access to the benefits of ML technologies.
  • Black Box Nature: A frequently cited drawback of many ML models, particularly those involving deep learning, is their “black box” nature. This term refers to the lack of transparency in how these models make decisions or derive predictions. The inability to easily interpret or understand the decision-making process of ML models poses significant challenges in critical applications where explainability is essential, such as in healthcare or legal decisions, potentially leading to trust and ethical issues.

Deciding Between Machine Learning and Heuristics: A Strategic Guide

Creating a cheat-sheet to navigate the decision between using ML and heuristics can simplify the complex process of selecting the appropriate approach for solving business problems. This is a checklist that I made based on my own experience.

Data Availability

  • Heuristics: Ideal when data is scarce, unstructured, or the cost and effort of collecting and preparing large datasets are prohibitive. Heuristics rely more on domain knowledge and expert insights rather than voluminous data, making them suitable for scenarios with limited data availability.
  • Machine Learning: Requires substantial amounts of structured, high-quality data. ML models excel when there’s ample data to learn from, allowing these models to uncover patterns and make predictions that would be impossible to program manually.


  • Machine Learning: If the goal is to achieve high accuracy and the task involves complex pattern recognition (such as image analysis, natural language processing, or predicting consumer behavior), ML models are likely to outperform heuristics. Their ability to learn from data can result in superior performance in many applications.
  • Heuristics: While not as powerful in handling complex pattern recognition, heuristics can be more efficient in simpler tasks where the logic is straightforward, and the computational cost needs to be minimized.


  • Heuristics: Offers high interpretability, as decisions are made based on clear, predefined rules. This makes it easier to understand and explain why a particular decision was made, which is crucial in fields like finance and healthcare, where decisions need to be justified.
  • Machine Learning: Certain ML models, especially complex ones like deep neural networks, often lack transparency in their decision-making process, making them less suitable when interpretability is a priority.


  • Heuristics: Because they are based on predefined rules, heuristics can be quickly adapted to changing business conditions or requirements without extensive redevelopment. This makes them particularly useful in dynamic environments where rules and priorities frequently shift.
  • Machine Learning: Adapting ML models to new conditions often requires retraining with new data, which can be time-consuming and resource-intensive. However, ML is more scalable and can handle a broader range of problems as data and conditions evolve.

Need for Human Intervention

  • Machine Learning: The automation capabilities of ML models can significantly reduce the need for human intervention, making them ideal for tasks that can be fully automated without direct human oversight. This is particularly valuable in applications where efficiency and scalability are priorities.
  • Heuristics: In scenarios where algorithms have a direct impact on human lives, or ethical considerations are paramount, reliance solely on unsupervised ML models may not be advisable. Heuristics, or supervised ML models with rigorous oversight, are preferred to ensure decisions are made with ethical considerations and human oversight.

Wrapping up

The essence of this decision-making process lies not just in comparing upfront costs or the technical elegance of solutions, but in deeply understanding the long-term value and cost-efficiency these technologies bring to the table. Machine learning, with its data-driven insights and automation capabilities, offers a powerful tool for businesses looking to scale operations and enhance decision-making processes. However, the significant investment required in data collection, processing, and model training, coupled with the need for specialized expertise, positions ML as a choice that necessitates careful consideration of its potential to generate a substantial return over time.

Conversely, heuristics, grounded in simplicity and domain expertise, stand out for their quick implementation and adaptability. The lower upfront costs and ease of modification make heuristics an attractive option for businesses seeking immediate improvements or solutions in data-constrained environments. Yet, the simplicity of heuristics may not suffice in scenarios demanding high accuracy and complex data pattern recognition, limiting their long-term ROI in certain contexts.

Thus, the decision to opt for machine learning or heuristics ultimately boils down to a comprehensive ROI calculation that accounts for not only the financial outlay but also factors in the value of adaptability, scalability, precision, and the potential for automation. This calculation should consider the direct and indirect benefits — such as increased efficiency, improved customer satisfaction, and the ability to innovate and maintain competitive advantage — against the backdrop of the organization’s strategic goals, operational needs, and the specific challenges at hand.

In the end, you might just need an “if statement”.