A Comparison of Large Scale Systems and Consumer Software Development

by Gloria Gery

The Need:

The assumptions underlying large scale software development are implicit and are rarely questioned. Those underlying assumptions drive development and design, including definition of the performer population and description of their work context. The assumptions must be made explicit so they can be discussed and either validated or changed.

The Chart:

The assumptions underlying consumer software development are quite different. And because those assumptions are so different, they drive a different design and development process. What Drives Software Development? A Comparison of Consumer vs. Large Scale Systems Development is designed to make these two differing sets of assumptions explicit so they can be compared and contrasted as part of the specification development process. The drivers for consumer software need to be adopted by large scale systems developers to improve the quality and power of software developed for organizational use.

Using the Chart:

Use the chart or components in proposals, functional specifications and presentations advocating performance centered design. Force open discussion about the design assumptions.

Rule of Thumb:

Developers and sponsors of new systems development have given little thought to these underlying assumptions and thinking in new ways must be facilitated.

 

Points of Comparison

Large Scale Systems

Consumer Software

Assumptions about users' and workplace knowledge:
  • Users will know the work and related concepts the software will be part of or support
  • Knowledgeable people will be available
  • Users will be trained prior to software use
  • Users will know limited interface conventions (e.g. use of buttons)
  • Users will not know content or task
  • Knowledgeable people unavailable
  • Training is unlikely
Development priorities:
  • Bug free code.
  • High integrity data
  • Accurate data transformation
  • Machine performance.
  • Matched to contracted client specifications (i.e. the client who pays the development or acquisition bills).
  • Architectural compatibility.
  • Operational performance.
  • On-time delivery.
  • Delivery within budget
  • System maintainability
  • Impact on task performance: making work easier, faster, better Market acceptability
  • Great word of mouth
  • Glowing product reviews by press
  • No implementation and training costs: Day One Performance
  • Negligible support requirements
  • Time to market
  • Bug free code
  • Reuse of code
  • Executable on installed hardware base or demonstrate such value that people will upgrade hardware to run software.
  • Maintainability
Implementation times

Performance expectations

  • Short to moderate for initial implementation Gradual utilization over time
  • Immediate implementation
  • Immediate performance outcomes
Assumed User Characteristics
  • Compliant to management directives
  • Captive. Cannot reject the software for an alternative
  • Resigned to difficult systems environments. Grateful for any improvements
  • Prefer on-time availability to usability and performance impact
  • Data driven
  • Willing and able to invest in learning
  • Not influential in the marketplace
  • Long term job tenure (past and future)
  • Time urgent
  • Impatient
  • Results oriented
  • Can reject software for marketplace alternatives or can return to non-automated task performance
  • Influential in the marketplace
  • Who will use the software will change over time; high user turnover or new user populations emerging
Design Goals
  • Conform to known standards (e.g. Windows-compliant)
  • Reflect current work processes
  • Similar to current systems and work requirements requiring only incremental change. Very different from the present is not a good thing.
  • Killer application with unique attributes and behavior.
  • Fundamentally alters how work is done. High payoff
  • Day One Performance by novice workers
  • Seductive and compelling to users. Create energy. Demand pull.
Measurements and Rewards based on:
  • On-time delivery
  • Development costs
  • Functionality meeting expressed customer requirements.
  • Technological superiority
  • System response time
  • Consumer (i.e. performer) acceptability and mindshare
  • Innovation
  • Impact on efficiency, effectiveness, value-added or business strategy
  • Profitability
Not accountable for:
  • Costs of implementation and ongoing support
  • Impact on results or business strategy
  • User satisfaction.
  • Open marketplace makes vendors accountable for all consequences