Guido van Rossum gave something like a TED talk on the history of Python. He explains why it is so important that code is easy to read and understand:
Typically when you ask a programmer to explain to a lay person what a programming language is, they will say that it is how you tell a computer what to do. But if that was all, why would they be so passionate about programming languages when they talk among themselves?
In reality, programming languages are how programmers express and communicate ideas — and the audience for those ideas is other programmers, not computers.