A Plea for Lean Software

An Essay by Niklaus Wirth

Software's girth has surpassed its functionality, largely because hardware advances make this possible. The way to streamline software lies in disciplined methodologies and a return to the essentials.

  1. ​Measured by the number of its features​
  2. ​Essential vs. nice to have​
  3. ​Dependence is more profitable than education​
  4. ​The most rewarding iterations​
  5. ​Never enough time​
  1. ​A grossly obese set of requirements​
  2. ​Features and complexity​
  1. Measured by the number of its features

    A primary cause of complexity is that software vendors uncritically adopt almost any feature that users want. Any incompatibility with the original system concept is either ignored or passes unrecognized, which renders the design more complicated and its use more cumbersome. When a system's power is measured by the number of its features, quantity becomes more important than quality. Every new release must offer additional features, even if some don't add functionality.

    Emphasis mine.

  2. Essential vs. nice to have

    Customers have trouble distinguishing between essential features and those that are just "nice to have." Examples of the latter class: those arbitrarily overlapping windows suggested by the uncritically but widely adopted desktop metaphor; and fancy icons decorating the screen display, such as antique mailboxes and garbage cans that are further enhanced by the visible movement of selected items toward their ultimate destination. These details are cute but not essential, and they have a hidden cost.

    /

    Increased complexity results in large part from our recent penchant for friendly user interaction. I've already mentioned windows and icons; color, gray-scales, shadows, pop-ups, pictures, and all kinds of gadgets can easily be added.

    1. ​Menus, Metaphors and Materials: Milestones of User Interface Design​
    2. ​littlebigdetails​
  3. Dependence is more profitable than education

    A customer who pays—in advance—for service contracts is a more stable income source than a customer who has fully mastered a product's use.

    Customer dependence is more profitable than customer education.

    What I find truly baffling are manuals—hundreds of pages long—that accompany software applications, programming languages, and operating systems. Unmistakably, they signal both a contorted design that lacks clear concepts and an intent to hook customers.

    1. ​The design concept​
  4. The most rewarding iterations

    Initial designs for sophisticated software applications are invariably complicated, even when developed by competent engineers. Truly good solutions emerge after iterative improvements or after redesigns that exploit new insights, and the most rewarding iterations are those that result in program simplifications.

    Evolutions of this kind, however, are extremely rare in current software practice—they require time-consuming thought processes that are rarely rewarded. Instead, software inadequacies are typically corrected by quickly conceived additions that invariably result in the well-known bulk.

    1. ​So that you can get feedback on it and make it better​
    2. ​To anticipate all the uses and abuses​
  5. Never enough time

    Time pressure is probably the foremost reason behind the emergence of bulky software. The time pressure that designers endure discourages careful planning. It also discourages improving acceptable solutions; instead, it encourages quickly conceived software additions and corrections. Time pressure gradually corrupts an engineer's standard of quality and perfection. It has a detrimental effect on people as well as products.

    1. ​Deadlines are bullshit​
    2. ​The Thing-deadline calculus​