Each individual must choose to be as safe as possible, but we also need to choose a culture that does not destroy progress. One example is Rick Fleeter, at Aero-astro, his company that builds micro satellites. Another is Burt Rutan, building composite prototypes such as Spaceship One.
I watched space shuttle Challenger blow up when I was in graduate school. Later, I listened to the news reports of Columbia, knowing a friend had been on board. All the safety processes and directives of NASA had failed to catch what only could have been done by an invidual. More problematic is the culture and bureaucracy that silenced people who were trying to be safe.
I wrote an article for Nuts & Volts magazine about the Space Ship One launches for the X-Prize that discussed these safety issues in greater detail.
Culture is a global optimization. Safety programs are a local minima.