This comes down to the cost of failure. If your app crashes or hangs sometimes, some of us might get annoyed but in the end we are all used to this now. It's a

This comes down to the cost of failure. If your app crashes or hangs sometimes, some of us might get annoyed but in the end we are all used to this now. It's a different story if your engine blows up from time to time. I am sure if every failure meant a 6 month and a million dollars setback, we would be designing software differently.