Understanding Systems Development Life Cycle 

In the information systems field, system failure can happen for several reasons, including missed deadlines, users’ needs that are not met, dissatisfied customers, lack of support from top management, and exceeding the budget. Old equipment, being unable to handle the capacity and pick times, also causes system failure. Using a system development method can help prevent these failures.
Designing a successful information system requires integrating people, software, and hardware. To achieve this integration, designers often follow the systems development life cycle (SDLC), also known as the “waterfall model.” It is a series of well-defined phases performed in sequence that serves as a framework for developing a system or project.
Systems planning today is about evaluating all potential systems that need to be implemented. A preliminary analysis of requirements for each is done, and a feasibility study is conducted for each system. Then the organization decides which ones are a “go” and proceeds to the next phase. Information system projects are often an extension of existing systems or involve replacing an old technology with a new one. However, sometimes an information system needs to be designed from scratch, and the SDLC model is particularly suitable in these situations.
For existing information systems, some phases might not be applicable, although the SDLC model can still be used. In addition, when designing information systems, projecting the organization’s growth rate is important; otherwise, the system could become inefficient shortly after it is designed. The planning phase is one of the most crucial phases of the SDLC model. The systems designer must define the problem the organization faces, taking care not to define symptoms rather than the underlying problem.
The problem can be identified internally or externally. An example of an internally identified problem would be management voicing concern about the organization’s lack of a competitive edge in the market-place. An example of an externally identified problem would be suppliers noting inefficiency in the inventory control procedure.