The behavioural finance literature has comprehensively documented the disposition effect, namely the tendency of investors to realise gains too readily and to defer the realisation of losses (Shefrin and Statman, 1985; Odean, 1998; Frazzini, 2006). This paper extends the analysis from the financial cost of disposition behaviour to the broader set of costs that losing positions impose on professional investors. It argues that the principal costs are not pecuniary but cognitive, behavioural, and organisational. Drawing on prospect theory (Kahneman and Tversky, 1979; Tversky and Kahneman, 1991), the limited-attention literature (Kahneman, 1973; Hirshleifer and Teoh, 2003), the empirical work of Akepanidtaworn, Di Mascio, Imas and Schmidt (2023) on institutional selling decisions, and the applied behavioural design framework of Schuller, Mousavi, and Gadzinski (2019), the paper proposes a structured, mandate-aware framework for managing losing positions. The framework rests on five principles: acknowledgement of full carrying cost, recognition of personal behavioural patterns, separation of entry and current decisions, structural pre-commitment, and process-based review. The paper also identifies a structural conflict between disciplined loss management and the calendar-driven incentive structures that govern professional asset management. Meaningful improvement requires architectural intervention rather than awareness alone.