Information Technology Reference
In-Depth Information
One could categorize them as “throwaway” or “reusable” prototypes.
The difference comes from the approach one chooses in building them:
horizontal or vertical slice. Throwaway prototypes are simple, quick, and
(possibly) dirty implementations of a concept. They are used to give an
overall feel of the final system, screen navigations, layouts, or the user
experience. They can be discarded post demonstration, and development
of the actual system will begin thereafter. Reusable prototypes, on the
other hand, form the basis of the final system — in fact, its foundation
in many respects. The idea is still to create a quick version of the system
but something where most of the prototype code will be reused as building
blocks. “Quick” in both cases is a relative word. It is not clear how much
time should be employed in creating prototypes. There is a notion of
percentages (similar to customizations) with respect to the time and
resources needed to create the entire system.
Life-Cycle Phases
There are many software development life cycles and many programming
practices in vogue. We believe that there is enough documentation regarding
the benefits and shortcomings of each. The missing piece, however, is to
determine how much weight should be given to each phase within the life
cycle. How should one distributes one's time and resources in the most
meaningful way, to get the maximum benefit? One way is through a cost-
benefit analysis of the tasks one plans to undertake in a life-cycle phase.
To succeed, one should decide on the preset goals (not features) for
each phase. It is imperative that the goals are clear and unambiguous.
They should be specific for that phase, as well as to the point. For example,
in QA one might start with a goal of “zero critical and serious defects in
the system.” The parameters on which one might do a cost-benefit analysis
would be:
Functionality that the customer believes is:
More important
More used
More visible
Has a bigger financial or safety impact
These parameters will help one narrow down one's goal and focus on
areas of immediate importance.
