(From Universal Principles of Desgin)
As the flexibility of the desgin increases, the usability and the performance of the desgin decreases
- Jack of all trades is master of none
- You can desgin something flexible to perform many different functions, at less cost, and at greater level of performance then more specialized desgins
- This is only true if and only if existing desgins are terribly inefficient
Explain: More flexible mean satisfing more conflicting requirements => which increases the compromises and complexity => which increases cost, degrades performance and usability
When these tradoff are valued:
- Is suboptimal good enough?
- Is the performance environment stable, meaning does it stay the same over time?
- Are performance and user requirements similar?
- Can functions be modularized in the design?
- Does the value of flexibility justify the performance tradeoffs?
Things that are aligned are percived to be more related then the things that are not aligned
- Things that are aligned lead the eye which influences the sequence in which people process the information
- Every element in desgin should align with atleast one another
- Disorder only to create emphasis or visual tension
A continous expansion or addition of new product feature beyond the original scope
-
Most common cause of project overruns
-
Factors:
- Features are easy or convenient to add
- Features accumulates over multiple generation of product
- Features are added to appease the stakeholders
-
Key Driver => More is better belief
-
Adding features adds complexity and complexity costs
-
How to avoid:
- Always be on the lookout for adding new features during the desgin and development of the product.
- Ensure that the features are linked to customer needs and not added out of convenience or appeasement
- During iterations, ask what can be subtracted along with new additions
- Create a milestone to FREEZE the product specification.
Traces of use or wear that indicate preferred methods of interaction
-
The road most travelled
-
Desginer centric desgin (where designer know the best way of thinking)
-
User centric desgin (deep understanding of how people will interace with a thing or product, and let that understanding guide and inform the desgin)
-
Desire Lines are noninvasive, unbaiseed and stastical measure of how people actually use a thing