This chapter uses the Diffusion of Innovations (DOI) theory and examines a business case, highlighting certain gaps in the theory. First, confusion can be present between the innovation construct (in this instance, replacing the enterprise systems) and the diffusion construct (that is, selling that innovation to upper management). Second, the business case has never been examined in diffusion research. Research about business cases generally focuses on techniques such as Discounted Cash Flows and Total Cost of Ownership. Third, although a good business case can lead to successful innovation, it should not influence upper management to be overly positive or too cautious. One extreme leads to over-commitment. The other extreme leads to under-commitment or upper management’s inability to commit. Both extremes have unexpected and undesirable consequences. This single-case study examined a business case. The data included in the triangulation are observations, in-depth interviews, and archival documents. The analysis of a business case document was done with the ATLAS.ti v5.0 software. It is hoped that understanding a “real world” business case will give the academics insights on the relationship between the innovation and its diffusion as well as teach the practitioners the caveats of a business case.
System development life cycle (SDLC) engulfs the whole system life cycle. Not only spanning over the feasibility study, analysis, specification, design, development; but also encompassing the aspects resonating in the operations, maintenance and enhancement, which would take place only after the system has been accepted by the end user.
Additionally, Project encapsulates the management environment set up, whereby ensuring delivery of specifically tailored business product to cater to a pre-defined business case. As such, Project does not cover all stages of system life cycle and covers mostly the technical deliverables.
Within this context, System development life cycle would be also denoted system process in software engineering as an integral part of IT project management. Highlighting the fact that many system development life cycles are developed to enable project managers to manage their project and overcome many constraints, inter alia: Money, Time, effort and Human resources. However, in view that two elements affect the project management apt choice of the SDLC; Familiarity of the project and the size of the project, whereas the authors use familiarity when referring to how familiar the project cadre is with the technology implemented in the project and the culture of the project, while the authors use the size of the project when referring to the time needed for project accomplishment, cost of the project, project people (users and development team), and the area of the project.
Accordingly, this chapter will discuss more than twenty SDLCs found in the IT project management arena, whereby, a comprehensive overview of the SDLCs history as well as the trigger that instigated its development would be laid out. Subsequently, the chapter will discuss the advantages and disadvantages of using SDLC, whereby the chapter will explain where and when to use which SDLC. As such, the chapter will classify the different SDLCs into three non-exclusive categories: Traditional methodologies, agile methodologies and spiral methodologies, of which the chapter will attempt to discuss some models as stipulated in Figure 1. (Figure 2)
System development life cycle taxonomy
Figure 2. Top
System development life cycle taxonomy (Adapted from Hoffer et al, 2005)
This section discusses nine renowned SDLCs: Waterfall, Incremental, V Model, b Model, Fountain Model, Prototyping, Relay Race Methodology (RRM), and Structured Systems Analysis and Design Method (SSADM).
In this regard, certain properties can be attributed to traditional SDLC; First, traditional SDLC is comprised of discrete phase. Second, each phase has a deliverable product at the end. As such, traditional SDLCs are usually used in large projects where the familiarity element is very high.