Many analysts of American and Japanese industry have attributed Japanese success at producing quality products to the fact that they emphasize incremental improvements, convenient features and quality rather than noteworthy inventions.
It is especially true in software that success depends primarily on getting the details right. And that is most of the work in developing any useful software system. Inventions are a comparatively unimportant part of the job.
The idea of software patents is thus an example of the mistaken American preoccupation with inventions rather than products. And patents will encourage this mistaken focus, even as they impede the development work that actually produces better software.