You want to actively elicit feedback from end users using short development cycles or by using prototypes and models during analysis. A good feedback cycle has the appearance of causing problems. It will cause emergent and latent requirements to surface. That means rework: the value of prototypes is that they push this rework back into analysis, where it has more value. And most important, good end user engagement changes end user expectations. It is only by participating in a feedback loop that’s grounded in reality that customers get the opportunity they need to reflect on what they’re asking for. If your customer changes their expectations in the process, you’ve both learned something. Embracing change doesn’t just mean reacting to it: it means providing the catalysts that accelerate it.