Background: Canadian neurosurgery residency programs have an alarming 28.4% attrition rate—seven times higher than the average for most other specialties (1–4%) and double that of US neurosurgery programs. Canadian data for this issue is over 30 years old, highlighting the need for updated research. This study identifies factors contributing to Canadian neurosurgery attrition rates. Methods: Using critical constructivist theory, virtual interviews were conducted with current program directors (PDs) from Canada’s 14 neurosurgery programs and neurosurgery residents who left training between 2013–2023. Interviews were recorded, transcribed, anonymized, and iteratively coded through descriptive thematic analysis to construct an analytical framework. Results: We conducted interviews with 7 PDs and 7 former neurosurgery residents, representing 7 neurosurgery programs across Canada. The average attrition rate was 14.11% (0%–28.6%) from 2013–2023. Contributing factors include poor job prospects in Canada, resource constraints leading to high workloads, poor work-life balance, moral distress due to high levels of patient mortality, and a lack of teaching and support from staff and senior residents. Conclusions: Neurosurgery residents are the future of neurosurgery. Our study uncovers factors contributing to high attrition rates in neurosurgery training, indicating that change must come from provincial governments and within training programs to retain residents.