> What specific things make it unwise to commit later? Examples, please.
Well, here's an example about why it's important to consider the navigation
I'm currently working on a large supply chain management application. When
the first modules of functionality were developed, they were given an MDI
navigation scheme. (Multiple document interface: every action happens in
it's own window.) This was identified as a problem, new navigation was
designed, and all new functionality is deployed within an SDI framework.
But what to do with the old functionality? It has be made to work within the
SDI framework we designed. All of the UI for the old modules has to be
re-written. This extra rewrite is six months of work that would not have to
be done had the navigation design been considered early on.
A note about process: the project in this example is not agile. Until I
joined, it did not have a user-centered nature either. So the example is
drawn from outside the scope of this discussion list, but is instructive
I do believe that if we were working within an agile context, the scope of
the rework would have been considerably smaller. I will claim that working
in a user-centered agile context, the cost of the rework would have been
zero--the problem could have easily been identified before a single line of
code was written.
So what's the point of the example? Just to illustrate that there are design
dependencies. Certain classes of decisions need to be made earlier than
In an earlier post, I wrote:
>> Finally, the earliest UX decisions blend into product definition and
>> strategy. What functionality is required? What is the product
>> emphasis? As an example, in an early case study from Cooper, they talk
>> about some scanner managment software they worked on for Logitech.
>> This utility accompanied a low-end sheet-feed style scanner, and was
>> conceived of as "scanner managment" software. Some user research
>> revealed that at this price point, no-one wanted to manage and
>> configure the scanner. Everyone simply wanted to use the scanner to
>> get images into Word. This insight, followed to it's conclusion,
>> radically changed the product requirements, the set of funtionality
>> that was included, and, of course, the nature of the user interface.
> The interesting questions here are:
>1) What functionality was common between the two kinds of scanners?
The scanners were the same. Only the management software changed.
The internal functionality of the process-centric software was a subset of
the scanner management software. The scanner management software include
rich scanner parameter adjustment capability. The Process-centric version
used 5 presets. The scanner management software allow image rotation in
1-degree increments within a 360-degree space. The process-centric version
allowed only 90-degree increments. Etc.
The process-centric version includes some UI features that the
scanner-management version did not. Image-cropping used a non-destructive
method, for example, and was invoked by a UI that was able to visualize this
(then non-standard) method of cropping.
> 2) How could the system have been built such that the decision to
> switch could have been made later - still with reasonable cost?
Don't know. I'm not in the construction business ;-)
> 3) How can the system be built such that *not* switching doesn't
> result in a lot of work with no payoff?
I'm not sure I understand this question. Can you clarify what you're asking?