Understanding the Cost of Poor Code Quality: Why Replacing a Bad Developer Can Be More Cost-Effective Than Fixing Flawed Work
In the software development industry, the quality of code can significantly influence project timelines, costs, and long-term maintainability. While it might seem easier or more cost-effective to keep a developer who has produced subpar work, real-world examples demonstrate that firing a poorly performing developer can save companies considerable resources in the long run.
This article explores two personal examples to illustrate the impact of bad coding practices and why replacing ineffective developers can be a strategic decision.
Case Study 1: Symfony API Project and Performance Pitfalls
The first example involves a small Symfony-based API project, which was my initial experience with this framework. The project’s goal was straightforward: provide endpoints to retrieve weather station data, specifically the most recent weather readings.
The endpoint /weatherstation/{id} was designed to fetch the latest weather entry per station. When no ID was provided, the endpoint returned data for all stations. However, issues arose because the developer had configured the API to retrieve all entries for each station rather than just the latest one. Considering the database contained approximately 30,000 entries per station, this resulted in massive data retrieval.
Notably, the API was online for a period—around mid-2024—and the slow response times became evident. The root cause? Sequential requests for each station, with response times ranging from 300ms to over a second, compounded by the fact that each call fetched all entries—about 150,000 entries in total—sending roughly 80MB of data to the frontend. This inefficiency led to sluggish page loads, with weather pages taking up to six seconds to display.
The repercussions? Currently, three developers spend substantial time fixing, optimizing, and rebuilding features initially crafted by one particularly problematic developer. Fixing these foundational issues is more time-consuming and costly than replacing the source of the flawed code.
Case Study 2: E-commerce Application’s Data Handling Failures
The second example comes from a freelance project—an e-commerce or inventory application. Over two years, performance concerns persisted, often tied to common issues such as N+1 query problems, which cause inefficient database access.
The most recent critical failure involved misordered product data, leading to incorrect delivery notes. The underlying problem was retrieving two separate lists of items from the database without ensuring their alignment—causing mismatched product quantities and erroneous data presentation.
Further complic
