[LINK] Software quality control metaphors [was: Knight of razor to slash government spending]

[Stephen Wilson]

grove at zeta.org.au wrote:
> On Fri, 25 Apr 2008, Stephen Wilson wrote:
> 
>> Unlike any other engineering, software does not obey the laws of 
>> physics. Writing software is much more like writing plays, than 
>> building bridges. Until the 'profession' comes to terms with this, I 
>> am sure quality and professionalism will remain elusive.
> 
> 
> There are some terrible, poorly written plays out there.
> But software, unlike a play can cause harm, or even physical injury.  
 > ... Standards need to be applied, even if they are only personal
 > standards and quality is important in everything.

I concur with the need for standards, for sure.  It's just that they are 
not sufficient.  What's also needed is structure, and many thought that 
this would result from OO, or CASE, or Formal Methods, or High Level 
Languages, or whatever the latest fashion was.  But experience shows 
that the innate desire of developers to create still supersedes the 
stricture of these tools and nullifies their benefits.

The reason why I liken software development to play writing is that I 
reckon structure in both cases is mostly arbitrary -- it comes from the 
composition (oh, and neither obey the laws of physics).  A good software 
engineer will know their composition from end to end. Yet another 
programmer can always come along and edit the work, inserting their own 
code as they see fit.  We all know that many if not most bugs arise from 
people modifying old code, with insufficient attention to the whole of 
the parts that came before.

Messing with a carefully written piece of software is fraught with 
danger, just as it is with a finished play.  I could take Hamlet for 
instance, and hack it as easily as I might hack an old program -- add a 
character or two, or a whole new scene -- but the entire internal logic 
of the play would almost certainly be wrecked.

Cheers,

Steve Wilson
www.lockstep.com.au