Psychological safety, a pivotal factor in team dynamics, has been proposed as a crucial determinant of success in agile software development (ASD) teams and learning. However, the extent of its influence within the domain of large-scale agile (LSA) software development teams remains underexplored. This research investigates the multifaceted dimensions of psychological safety within LSA teams, examining both its precursors and outcomes. This study conducted semi-structured interviews with software professionals actively involved in LSA projects within a Swedish software consultancy company. The findings underscore the intricate nature of establishing a psychologically safe environment within LSA teams, revealing it as a multidimensional construct necessitating a proactive leadership approach, fostering open communication, and cultivating an ecosystem of constructive feedback. The study highlights the critical importance of intentionally shaping teams to facilitate continuous learning, ensuring remuneration safety, and implementing a comprehensive onboarding process for incoming team members. By fostering psychologically safe settings, LSA teams enhanced teamwork dynamics, heightened job satisfaction, and facilitation continuous learning and development. Notably, the absence of such an environment exacerbates the phenomenon of brain drain, exposing the tangible consequences of overlooking this fundamental aspect of organizational culture. This study proposes avenues for future research directions, aiming to further unravel the nuances of psychological safety and its cascading effects within the realm of contemporary LSA software development context.