This study investigates the professional development (PD) of teachers in private schools in Turkey, exploring how it functions as a form of adult education. Employing a qualitative research approach with thematic analysis, semi-structured interviews were conducted with teachers, school leaders, and PD providers to understand motivations, participation patterns, and budget allocations related to PD with an aim of understanding how these reflect broader trends. The findings reveal that PD is heavily influenced by external motivations such as school leaders, job security, and networking opportunities, often driven by market strategies rather than educational needs. While intrinsic motivations related to personal growth and societal contributions exist, they are significantly overshadowed by external factors. The study also examines the types of PD activities, emphasising a shift towards trend-driven content that aligns more with marketing strategies than with educational enrichment. This trend underscores the commodification of PD, aligning it with institutional branding and market competition, thus challenging the foundational goals of adult education and teacher empowerment.