This chapter highlights the often overlooked or underestimated obstacles that can impede the thriving of animals under human care. This chapter critically examines the internal and external factors that contribute to these pitfalls, providing a nuanced understanding of the multifaceted nature of animal welfare. Key themes include the identification of species-specific and individually specific challenges, the impact of environmental and historical variables, and the strategies for mitigating these issues to enhance animal welfare. The chapter also discusses the importance of comprehensive behavioural and physiological assessments in identifying and overcoming these barriers, emphasising a holistic approach to animal care that goes beyond basic survival to ensure psychological, emotional, and social thriving.