EXPLORING REQUIREMENTS – QUALITY BEFORE DESIGN

Gause & Weinberg - PART IV – CLARIFYING EXPECTATIONS

Clarifying ExpectationsDefine these and streamline at every step

FunctionsAttributesConstraintsPreferencesExpectations

FunctionsDefine the functions - what should the

product DO to exist for the client?

Apply function heuristics - categorize functions into evident, hidden and frill

Do this each time you decompose a function into lower-level functions

AttributesCharacteristics desired for a function

Function = durability for an eraserAttributes = absorbing capacity; capacity to

not smudge while erasing; not break when dropped

Wish list – organize – assign to functions

Exclude non-assigned ones

ConstraintsAfter all functions are defined, attributes are assigned to

functions & classified…

See if attributes are implemented….how? If all its constraints are satisfied, an attribute is

implemented

Constraint – a mandatory condition or a rule for an attribute

Example: for eraser: constraint=made of unbreakable material not glass;

Test these constraints

Preferencesdesirability in solutions

Preference can also become an attribute (e.g., color preference)

Analyze within the context to see if it becomes a constraint that can be doable or not

Example: for eraser – should have a wooden base and a green color on surface

ExpectationsHow well your product matches the client’s

expectations

Expectations need to be monitored and managed at every stage

Expectation limitation processGenerate list of expectationsRevise and Optimize the listLimit the expectations – possible, deferred, absolutely

not possible