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Which development methodologies are used to build systems, and how are feasibility and fact-finding carried out?

Development methodologies (waterfall, prototyping, rapid application development and agile), the feasibility study, and fact-finding techniques.

A CCEA A-Level Software Systems Development answer on development methodologies (waterfall, prototyping, rapid application development and agile), conducting a feasibility study, and fact-finding techniques such as interviews, questionnaires, observation and document analysis.

Generated by Claude Opus 4.813 min answer

Reviewed by: AI editorial process; not yet individually human-reviewed

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  1. What this dot point is asking
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What this dot point is asking

CCEA expects you to compare development methodologies - the waterfall model and iterative approaches such as prototyping, rapid application development (RAD) and agile - giving the strengths and weaknesses and the kind of project each suits. You must also describe the feasibility study (is the project worth doing?) and the fact-finding techniques used in analysis. Comparing waterfall with iterative methods, and listing fact-finding techniques with advantages, are favourite questions.

The answer

The waterfall model

Its weakness is inflexibility: because requirements are fixed up front and the model flows once, a change late in the project is costly, and users do not see working software until late, so a misunderstanding can go undetected for a long time.

Iterative methodologies: prototyping, RAD and agile

The defining contrast: waterfall fixes requirements and proceeds once; iterative methods revisit and refine through cycles.

Feasibility study and fact-finding

A feasibility study, done early, asks whether the project is worth pursuing, judged on technical (can it be built with available technology?), economic (do benefits outweigh costs?), legal, operational (will it fit how the organisation works?) and schedule (can it be done in time?) feasibility.

Fact-finding during analysis gathers requirements using:

  • Interviews - in-depth, with follow-up questions (detailed, qualitative).
  • Questionnaires - many users quickly and cheaply (comparable, quantitative).
  • Observation - what users actually do, revealing real workflows.
  • Document analysis - existing forms, reports and files, showing real data and outputs.

Worked example: choosing a methodology and planning fact-finding

Examples in context

Example 1. A payroll system uses waterfall. Payroll rules (tax, pension, hours) are well defined and stable, and the system must be thoroughly documented for audit. The waterfall model suits this: requirements are fixed early, each stage is completed and signed off, and clear milestones make the project easy to manage, with little need to revisit decisions.

Example 2. A consumer app uses agile. A new social app faces uncertain, fast-changing requirements. Agile delivers a basic version, then adds and refines features sprint by sprint based on user feedback and analytics. Early prototypes test ideas cheaply, and the team can pivot when the market reacts, which a one-pass waterfall could not accommodate without expensive rework.

Try this

Q1. State one advantage and one disadvantage of the waterfall model. [2 marks]

  • Cue. Advantage: simple to manage and document with clear milestones, suiting stable requirements. Disadvantage: inflexible to changes and users see working software only late.

Q2. Name two fact-finding techniques and give one advantage of each. [4 marks]

  • Cue. For example interviews (detailed, qualitative, allow follow-up) and questionnaires (gather from many users quickly and cheaply, easy to compare).

Q3. State two areas a feasibility study examines. [2 marks]

  • Cue. Any two of technical, economic, legal, operational and schedule feasibility.

Exam-style practice questions

Practice questions written in the style of CCEA exam questions on this dot point, with worked answer explainers. The year tag is the paper they imitate, not the source.

CCEA 20186 marksCompare the waterfall model with an iterative approach such as prototyping or agile, giving one advantage of each.
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The waterfall model is a linear, sequential methodology: each stage (analysis, design, implementation, testing, installation, maintenance) is completed before the next begins, ideally without going back. An advantage is that it is simple to manage and document, with clear milestones and deliverables, which suits projects with stable, well-understood requirements.

An iterative approach such as prototyping or agile builds the system in repeated cycles, producing working versions early and refining them with user feedback. Prototyping builds a quick model of the system for users to try, then improves it; agile delivers the system in short increments (sprints), responding to changing requirements throughout. An advantage is flexibility: requirements can change as users see and react to working software, and problems are found early, which suits projects where the requirements are unclear or likely to change.

The key contrast is that waterfall fixes requirements up front and proceeds once, whereas iterative methods revisit and refine through cycles with continuous user involvement.

Markers reward a correct description of waterfall (linear, sequential, requirements fixed early) and of the iterative method (cyclic, feedback-driven), with a genuine advantage of each.

CCEA 20215 marksDescribe three fact-finding techniques an analyst could use during the analysis stage, and state one advantage of each.
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Fact-finding gathers information about the current system and the requirements. Three techniques:

Interviews involve talking to users and managers, asking prepared questions. An advantage is that the analyst can ask follow-up questions and explore issues in depth, getting detailed, qualitative information.

Questionnaires send written questions to many people. An advantage is that they gather information from a large number of users quickly and cheaply, and the responses are easy to compare and quantify.

Observation involves watching users perform their tasks. An advantage is that it shows what people actually do (rather than what they say they do), revealing real workflows, bottlenecks and informal practices.

A fourth valid technique is document analysis (examining existing forms, reports and files), whose advantage is showing the real data and outputs the current system uses.

Markers reward three genuine techniques (from interviews, questionnaires, observation, document analysis, meetings) each with a correct, distinct advantage.

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