How Much Time Do Developers Lose to Technical Debt? A Replication Study Reveals 23% Waste

1. Introduction

This article, published in Journal of Systems and Software in October 2019, investigates Technical Debt ( TD) and its impact on software developers' productivity.

The study uses longitudinal surveys and interviews to quantify the time waste caused by technical debt and provides empirical evidence for its management.

25% of developers' work time is wasted .

Extra code analysis is strongly linked to time waste.

In 25% of cases, existing technical debt forces developers to introduce new debt.

Developers are more aware of the wasted time than managers.

2. Research Background and Objectives

Impact of Technical Debt

Technical debt refers to short‑term shortcuts in software development (e.g., simplified design, rushed coding) that can increase maintenance costs and reduce development efficiency over time. While its negative effects are theoretically clear, empirical data on specific time loss and productivity impact have been lacking.

Research Objectives

The study aims to quantify the development time lost to technical debt, analyze which activities consume this time, examine the types of debt involved, and compare developers' and managers' perceptions of the waste.

3. Research Methodology

Longitudinal Survey

43 developers were surveyed twice weekly for 7 weeks, recording time lost to technical debt, the activities involved, and the debt types.

Interviews

16 developers were interviewed to gain deeper insight into the mechanisms of technical debt’s impact.

Replication Validation

An independent dataset was used to replicate the study and verify the reliability of the initial findings.

Triangulation

Source triangulation (different times/subjects), observer triangulation (multiple researchers), and method triangulation (survey + interview) were combined to increase result credibility.

4. Core Findings

1. Time waste proportion Developers waste on average 23% of their work time due to technical debt, with considerable individual variation. This result was confirmed in the replication study, indicating a universal negative impact on productivity.

2. Main waste activities Wasted time is primarily spent on extra testing, source‑code analysis, refactoring, and manual handling of processes that could be automated.

3. “Contagion” of technical debt In about 25% of cases, existing technical debt forces developers to introduce new debt (e.g., further simplifying code to meet urgent needs), creating a vicious cycle.

4. Perception gap Developers perceive the time loss from technical debt more strongly than managers, revealing inconsistent awareness within organizations.

5. Impact of debt types All debt types (code, design, documentation, etc.) cause time waste, but code‑related and architecture‑related debt have the most pronounced effect.

5. Discussion and Implications

For Practitioners

Technical debt leads to significant productivity loss; organizations should prioritize debt management (regular refactoring, comprehensive documentation) and foster a shared understanding between developers and managers to avoid underestimating long‑term costs.

For Researchers

This is the first longitudinal quantification of technical debt’s time cost, offering a methodological reference for future work. Subsequent research could explore the specific impacts of different debt types and effective repayment strategies.

6. Contributions

Empirically quantified the proportion of time wasted due to technical debt, bridging the gap between theory and practice.

Identified the “contagion” characteristic of technical debt, providing a new perspective on debt accumulation mechanisms.

Validated findings through replication, enhancing the generalizability of the conclusions.

Original Link

Software developer productivity loss due to technical debt—A replication and extension study examining developers’ development work (https://www.sciencedirect.com/science/article/abs/pii/S0164121219301335)