Despite growing global recognition of bioshields as effective nature-based solutions, numerous initiatives across Asia have encountered significant challenges and mixed outcomes. This chapter critically examines the failures, limitations, and lessons learned from bioshield projects in the region, drawing on case examples from Southeast Asia. It identifies key ecological, technical, and socio-political factors that have constrained success, including inappropriate site selection, monoculture planting, insufficient community involvement, and weak institutional coordination. The chapter also explores how overreliance on donor-driven short-term projects and inadequate post-implementation monitoring often lead to ecosystem degradation and loss of local trust. Ecologically, failed projects reveal the consequences of ignoring hydrological regimes, soil salinity, and species–site compatibility. From a governance perspective, fragmented policies, overlapping mandates, and inconsistent enforcement hinder sustainable outcomes. Socially, neglecting traditional knowledge and local participation has frequently undermined legitimacy and maintenance. Yet, these failures offer valuable insights. The chapter synthesizes key lessons learned, emphasizing adaptive management, stakeholder inclusion, and integrated coastal planning as essential pathways for future bioshield success. By comparing failures and recoveries across Asian nations, it highlights the evolution of bioshield strategies from experimental restoration to mature ecosystem-based management. Ultimately, this chapter underscores that recognizing and learning from past shortcomings is critical to advancing resilient, inclusive, and scientifically grounded coastal protection frameworks across the region.