The interaction between systems and teams is bi-directional. Conceptually a team may step in to perform the role of a system – as a manual work around in case of system failure or outage; and vice versa, a system may step in to perform the role of a team – when a previously manual activity is automated, or as an automatic emergency response to a human failure or accident. Mathematically, the relationship between systems and teams is symmetric.
In abstract terms, both systems and teams can be thought of as actors that perform one or more roles. The distinction between systems and teams is one of convenience, to inform the reader of a model about the levels of automated and human decision making in a given context.