Bank machines would not be at all useful unless they opened your bank account - and only your bank account. Some of the simplest technologies succeed because they are personalized. Personalized housing is made possible with personalized keys, another good technology. Things like credit cards, smart cards, pagers, cell phones and eyeglasses are other examples. Bad technology forces you to fit its requirements.
Good technology is modular .
By 'modular' I mean composed of distinct parts which may be arranged or rearranged into a desired configuration with a minimum of fuss and effort. To a degree, this requirement is a combination of the 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 configuartions. The stereo systems we purchased in the Seventies were good examples of modular technology. Good technology does what you want it to do .