Nothing is perfect, and there are (quite a few) disadvantages to a projectized structure (this is why a lot of traditional organizations have not adopted this type of structure). Disadvantages include:
- Since resources are allocated to the same type of projects, there is no cross-fertilization of the resources, meaning that resources will not gain experience from other departments in the organization. This leads to two direct problems: 1) Efforts are duplicated across projects, and 2) resources are demotivated as they're always working on the same kind of projects.
- Very hard to implement especially in traditional organizations, as it doesn't consider the current role and the weight of the managers, and completely shuffles all the roles and the responsibilities.