Everything takes longer than ppl want to wait. But when building a house, ppl are more patient and tolerant about the time taken, because they can physically see the progress, the effort, the sweat. Software is intangible and invisible except maybe for beta-testers and developer liaisons. And the visual parts, like the nonfunctional GUI or web UI, are often taken as "most of the work is done", because that is what people see and interact with.

It's product management's job to bridge that gap. Break down and prioritize complex projects into smaller deliverables that keep the business folks happy.

It's better than houses, IMO - no one moves into the bedroom once it's finished while waiting for the kitchen.