Drawing from experiences at Amazon, the author shares insights into the complexities of caching, emphasizing that while caching can enhance scalability and performance, it should not be adopted hastily without careful consideration. Caching introduces additional layers of complexity, such as potential delays and errors if poorly implemented, and requires thorough planning, sizing, and instrumentation before integration. The blog explores the challenges of low cache miss rates and the effects of stale data, encouraging explicit strategies like setting TTLs to manage cache staleness. It contrasts local caching, which can lead to scalability issues in larger systems, with separate cache fleets that, while offering shared intelligence and efficiency, bring their own set of challenges, including the need for meticulous management and proper client configuration to handle timeouts and connection issues. Ultimately, the blog advocates for deliberate and strategic decisions in caching, underscoring the importance of aligning caching practices with specific system needs to maintain cost-effectiveness and performance.