Sunk Cost Fallacy

Sunk Cost Fallacy: Understanding and Mitigating Its Impact in UX Design

The sunk cost fallacy is a cognitive bias where individuals continue an endeavor or project due to the cumulative prior investment (time, money, resources) despite new evidence suggesting that continuing is not the best course of action. In UX design, this bias can affect decision-making, leading to suboptimal user experiences and wasted resources.

What is the Sunk Cost Fallacy?

The sunk cost fallacy occurs when people make decisions based on previously invested resources rather than on current and future benefits. This fallacy can cause users and designers to persist with outdated, inefficient, or unproductive systems and processes because of the time and effort already spent.

Importance of Recognizing the Sunk Cost Fallacy in UX Design

  1. Improved Decision-Making: Recognizing the sunk cost fallacy helps designers make more rational decisions based on current data and user needs rather than past investments.
  2. Resource Optimization: Avoiding the sunk cost fallacy ensures that resources are allocated effectively, focusing on features and designs that provide the most value to users.
  3. User Satisfaction: Designing based on current user needs and feedback, rather than sticking to outdated concepts, improves user satisfaction and engagement.
  4. Innovation Encouragement: Being aware of this fallacy encourages teams to embrace change and innovation, leading to better and more competitive products.
  5. Project Success: Mitigating the impact of the sunk cost fallacy increases the likelihood of project success by focusing on what works best rather than what has been done.

Key Strategies for Mitigating the Sunk Cost Fallacy

  1. Data-Driven Decisions: Base decisions on current data, user feedback, and usability testing rather than past investments.
  2. Iterative Design: Embrace an iterative design process that allows for regular testing, feedback, and adjustments, focusing on user needs and market changes.
  3. Set Clear Objectives: Define clear, measurable objectives for each project phase, helping teams focus on outcomes rather than past efforts.
  4. Encourage Open Communication: Foster an environment where team members feel comfortable voicing concerns and suggesting changes, even if it means abandoning past work.
  5. Regularly Review Projects: Conduct regular reviews and assessments of ongoing projects to determine if they are meeting current goals and user needs.
  6. Prioritize User Needs: Always prioritize user needs and feedback over past investments. This ensures that the design remains relevant and user-centric.

Best Practices for UX Designers

  1. Acknowledge the Fallacy: Educate team members about the sunk cost fallacy to raise awareness and reduce its impact on decision-making.
  2. Focus on ROI: Evaluate the return on investment (ROI) of continuing a project versus pivoting to a new approach based on current data.
  3. Be Willing to Pivot: Encourage a culture that is willing to pivot and change direction when necessary, even if it means discarding previous work.
  4. Document Decisions: Keep a record of decisions and the rationale behind them. This can help in evaluating whether to continue a project or change course.
  5. User-Centered Design: Always prioritize the user experience in design decisions, ensuring that changes or continuations are in the best interest of the end user.

Tools for Mitigating the Sunk Cost Fallacy

  1. User Testing Platforms: Tools like UserTesting and Lookback allow for regular user testing and feedback, ensuring decisions are based on user needs.
  2. Analytics Tools: Google Analytics, Hotjar, and Mixpanel provide data on user behavior and engagement, helping to make informed decisions.
  3. Project Management Software: Tools like Jira, Trello, and Asana facilitate regular project reviews and updates, helping teams stay focused on current goals.
  4. Collaboration Platforms: Platforms like Slack, Microsoft Teams, and Miro encourage open communication and collaboration, fostering a culture of transparency and adaptability.
  5. Documentation Tools: Tools like Confluence and Notion help document project decisions and rationales, providing a reference for future evaluations.

Real-World Examples

  1. Product Redesigns: Companies like Apple regularly redesign their products based on current market trends and user feedback, even if it means discarding previous designs.
  2. Software Updates: Platforms like Microsoft Windows and Adobe Creative Cloud continuously evolve, incorporating user feedback and abandoning outdated features.
  3. Website Overhauls: E-commerce giants like Amazon frequently update their website design and functionality based on user data and behavior analytics, rather than sticking to older designs.
  4. Feature Prioritization: SaaS companies like Slack prioritize features that enhance user experience and productivity, even if it means removing or replacing less effective ones.
  5. Marketing Campaigns: Companies like Coca-Cola regularly evaluate and change their marketing strategies based on current data, regardless of past investments.


Recognizing and mitigating the sunk cost fallacy is crucial in UX design to ensure that decisions are made based on current and future benefits rather than past investments. By focusing on user needs, embracing iterative design, and fostering open communication, designers can create more effective and user-centric products. Implementing best practices and using the right tools ensures that the impact of the sunk cost fallacy is minimized, leading to better decision-making and more successful projects.

Ondrej Zoricak
Ondrej Zoricak