Information Technology Reference
In-Depth Information
it says that one is in the early stages of the project. As in the human
development life cycle, earlier stages require greater care and nurture than
later ones. One should take extra time and effort with specifications and
design before going on to the other stages. This is recognized in terms
of rework costs, which are higher, particularly if a change must be made
later. Uniform allocation of resources across all stages of a life cycle is
neither required nor advisable.
Plans and Life Cycles Are Different
A life cycle is rarely detailed enough, which it should not be, to constitute
a plan. Life cycles, however, can be used as a framework to develop
better plans. If the life cycle is frozen
, it can define the starting
granularity of a plan — requirements, design, development, etc. Each of
these can then be treated as phases of the plan and expanded in more
detail. A detailed plan may appear, at times, to be distorting the life cycle.
For example, if the plan is based on the waterfall life cycle, some aspects
of the testing, such as the development of a test plan, may be pulled
ahead in the plan. Life cycles help in higher-level understanding of what
is involved. Planning helps in working out the details. It brings into the
life cycle an element of viability and realism.
To arrive at a proper plan requires one to select the appropriate life
cycle. One of the reasons why plans fail is the “wrong” or poorly
understood life cycle being used as the underlying framework. As they
say in the military, “The map is not the territory.” Similarly, in software,
the plan is not the project — for that matter, the life cycle is not the
project either. Life cycles and plans are models, abstract approximations
that serve a purpose, but must not be confused with reality.
a priori
Planning Does Not Work in Firefighting Situations
Dwight Eisenhower said, “Plans are useless; planning is priceless.” (
Source:
A speech to the National Defense Executive Reserve Conference in Wash-
ington, D.C., November 14, 1957.) While true in most situations, it hardly
works in emergencies. There is a great difference because while planning
for an emergency, you must start with the very definition of “emergency”
— as it is unexpected, it will, in all probability, not happen the way you
are planning.
Most IT and software support is about firefighting and heroics.
