Uber's article [1] linked on the page mentions it at the start:
> These nonfunctional feature flags represent technical debt, making it difficult for developers to work on the codebase, and can bloat our apps, requiring unnecessary operations that impact performance for the end user and potentially impact overall app reliability.
> Removing this debt can be time-intensive for our engineers, preventing them from working on newer features.
> These nonfunctional feature flags represent technical debt, making it difficult for developers to work on the codebase, and can bloat our apps, requiring unnecessary operations that impact performance for the end user and potentially impact overall app reliability.
> Removing this debt can be time-intensive for our engineers, preventing them from working on newer features.
[1] https://eng.uber.com/piranha/