The logic of electronics miniaturization is that as we achieve ever higher levels of integration and hence simplification and miniaturization, every product becomes cheaper, more reliable and more useful. The smaller color TV freed of the AC umbilical cord can accompany you to a baseball game or onto the bus to work. Portable color monitors power cell phones, automated teller machines, aircraft cockpits and laptop computers. Billions of dollars of business have been created by miniaturized products doing the work of their older, bulkier and more expensive counterparts. Space devices have additional and stronger motivations to be small, low power and lightweight.
Power is arguably the largest single driver for spacecraft cost.
Reliability is paramount to space systems, which must operate for years without physical human contact. With 40 years of experience finding ever more complex and expensive roles for macrosatellites, we have barely started the search for the new applications microspace might enable. The logic of microspace is seeing spacecraft not in terms of program requirements and specifications, but via the trajectory they can evolve through and the enhanced and new applications they will one day enable. Every technical product and service we consider indispensable today started out as an expensive, unreliable, complex and largely useless curiosity, exciting mainly for its almost self-defining oddity. This description would include the early automobile, aircraft, telephone, electric light bulb, bicycle, computer, radio, cardiac artery bypass, air conditioner, microwave oven, organ transplant, and ballpoint pen.