This position paper takes as outset experience obtained during development of an object-oriented prototype for a global customer service system. The project involved a large shipping company and a university research group. The nature of the system development process: many, short iterations, shifting requirements, evolution over a long period of time, and many developers working in parallel, forced us to constantly focus on software architecture. By analysing the evolution of the prototype architecture we point to three characteristics of the development process that make exploitation of software architectures crucial in rapid, experimental system development, namely: