Still, insofar as they must be replaced, and are essential to the operation of a technology, they are parts. The less you have to purchase or replace, the better your technology, while the best technology requires no ongoing purchases or replacements at all. Perhaps even good technologies, such as portable stereos, need parts, such as CDs. DVD players, for example, are not good technologies until DVD disks become widely available. Programs that require complicated start-up routines are not as good as those that one can start with a single command.
Good technology is personalized.
One thing that makes a telephone useful is that you have your own telephone number. Bad technology forces you to fit its requirements. Good technology is modular. To a degree, this requirement is a combination of the two requirements that good technology be standardized and personalized, but modularity takes technology a step beyond either of those features. Bricks and wood are good technology, for example, because they interconnect neatly and can be assembled into custom configurations.