Instead of counting bugs per line of code, consider counting bugs per
second. A typical program environment on a PC may execute a few
BILLION instructins per second. So if it runs for 10 seconds and gets
the right answer, it has run, defect free, for something like 40
billion instructions. Impressive.
Or maybe not?

If a bug falls in the forest but no one hears it, does it make any
noise?

RJF