In the space shuttle, almost every bug could kill an entire crew. For Microsoft, a bug may cause a desktop to crash. Arguably, Microsoft wastes the most potential because many millions of instances of Microsoft software repeatedly waste a few minutes of people's lives.

The difference is that Microsoft is able to externalise almost all risk and accountability. The same principles of "defect management" are applied to aerospace hardware and Microsoft software. The only difference is the acceptable threshold for bugs. For the space shuttle, bugs are minimised until the budget is exhausted. For Microsoft, bugs are minimised until it costs less to to say "Oh, heck. Just ship it."