Facts about success of software and IT projects: Numbers remain »constant« for 20 years
successful = Project met all 3 of 3 constraints: scope, schedule, and cost
challenged = Project met only 2 of 3 constraints: scope, schedule, and cost
failed = Project was canceled before completed or completed but not used
Source: Chaos Report-Studie, Standish Group 2012-2015
Processes and their activities control all progress in departments, service, development, research, operations, support, etc. Each company determines which processes and activities have to be performed. Processes in the area of Software & IT Services have different characteristics and are differentiated by their characteristics agile, iterative, sequential or hybrid.
Process models define stages, phases, activities, roles, and artifacts, as well as the dependencies of activities, their degree of parallelization, the distribution of roles etc. Process models have a very different impact on effort, schedule, and costs. However, this impact is completely independent of the size of a project (see Methods & Metrics).
Typical examples of generic process models (implementation models) in software development are e.g. DevOps, Rapid Application Development (RAD), Rational Unified Process (RUP), Scrum, V-Model XT, Waterfall, etc. and in the field of IT services e.g. ISO / IEC 20000, ITIL v4, etc. A typical example of a specific process model is e.g. SAP ASAP 8 HANA.