The second tenant of business driven delivery (BuDD) is to integrate early and often. You also need frequently show something to the different stakeholders – e.g. management and customers. The reason for the focus on integration is to make sure that folks aren’t off developing in parallel components that just won’t work together like in this example: http://www.theguardian.com/world/2014/may/21/french-railway-operator-sncf-orders-trains-too-big. This helps make sure you are building things right.
To ensure that you end up delivering the right thing – you need to continually demo the evolving system to the stakeholders. This helps in two ways – you get feedback about what isn’t right, and buy-in to the final product.