[SystemSafety] Software reliability (or whatever you would prefer to call it)

[Martyn Thomas]

I'm puzzled by much of this discussion. Consider this common example:

A company creates a software package and submits it for beta testing by
a group of users. Assume that the package reports how often it is used
and for how long, and the users report all errors they encounter. Assume
there is a single instance of the software on a server that all the
users use.

The company corrects some of the errors that are reported.

The company calculates some measure of the amount of usage before
failure. Call it MTBF.

The MTBF is observed to increase.

What word shall we use to describe the property of the software that is
increasing?

I'd call it "reliability". If you would, too, then how can software
reliability not exist?

I don't mind if you want to use a different word to describe the
property. Let's just agree one, do a global replace in the offending
standards and move on ...

... to discussing a practical upper bound on the "reliability" that can
be assessed in this way - and on the assumptions that should be made
explicit before using any such assessment as a prediction of future
performance.

Martyn