Because it is hard to define what the complex system is, it is better to define the characteristics of the complex system. The more of them the system satisfies, the more the design process and the user interfaces of such systems are different compared to general mass-market systems.
- Usage for work purposes
Most complex systems are used at work or in a home office. While there are exceptions, these systems are typically recognized as the tools of a work process.
- Errors criticality
Misproper functionality or human errors lead to harmful consequences. These consequences can result in financial losses, threatening to health or life.
- Complex subject matter
The subject matter is complex, existed before the system produced, or is not defined by the system itself (compare with mass-market instant messaging apps).
- The object of automation is external to the system
Typically the system is automating some external processes or objects, like the safety of maritime navigation, the health of a patient, or the nuclear plant processes. In these cases, we may talk about the automated system (external, “natural” one) and the automation system (the “digital” one).
- Efficiency is more important than ease of learning
Most complex systems have a fairly high entrance barrier, but typically it results in making the stuff in a more efficient and powerful way.
- The user is not a buyer
Large-scale systems are typically expensive and the decisions about the purchase of a particular system are made at the management level. Typically it makes all the marketing methods very different compared to mass-market systems, where the user is also the buyer. Also, it can result, that the user of the system can be negatively motivated.