This study investigates the phenomenon of bug seeding in open-source software development, with a focus on how and when bugs are introduced into the source code. Previous research often assumes that the bug is introduced in the commit preceding the bug fix. However, our large-scale observational study on the OpenStack project challenges this assumption. By analyzing 459 bug reports and tracing their origins, we reveal that only 50% of the previous commits caused the system failure, while other bugs resulted from unrelated changes such as API modifications. The study provides insights into patterns of bug introduction and lays the groundwork for future efforts to classify and prevent bugs that are not directly linked to recent commits. These findings aim to improve bug detection and prevention mechanisms in open-source development.