One approach that I've found successful is this:

We all know that a computer does only and exactly what it is told to do.

Programming is the way that we tell a computer now what we what it to do later.

This means that the way your behaviour behaves now is due to the combined intentions of everyone who wrote any of the code that is running on your machine. When you consider the complexity of the operating system, drivers, programming environment, libraries and so on, it's easy to see that in most systems there must be upwards of 20k people involved, and that there could be over 100k.

The code written by each person reflects their own understanding, motivation, intention and capability. Given that flawless operation of the system requires that all of the code written by these 20k people interacts without error - that all of the code must agree on the meaning and interpretation of the required behaviour, the suprising fact is not that we have bugs, but that we have so few of them.