Designers and developers try to build stable and multi-domain software components while the software infrastructure they use keeps evolving and thus being heterogeneous. This can be called “the business and technical life cycles mismatch”. The paper shows where and why middleware technologies fail to solve the business and technical life cycles mismatch. Then it demonstrates that lots of the nice features of software components are allowed thanks to the concept of container. The container is an entity visible as much during software component development as during execution. Some of its properties must be taken into account in software architectures and design models.