A practical way to discuss caching trade-offs without handwaving

Most cache discussions begin with a diagram and end with the word 'Redis.' The useful conversation starts earlier: what is expensive, what can be stale, and what happens when the cache lies?

I have found a simple sequence helpful: define the read path, quantify the pain, set a freshness contract, choose an invalidation owner, and describe the fallback. It keeps the design anchored to a product decision rather than a tool.