It's a natural reaction for any creative to keep their work under wraps until it's ready, but ready is relative to the medium (and the creator).

Having worked professionally as an illustrator before becoming a programmer, I can confidently argue most illustrations don't look close to complete until you've laid down 95% of the paint. If you've worked all week on an illustration, and it doesn't meet your expectations, more often than not you need to begin with a clean canvas.

Code, on the other hand, can be functional in as little as one line. Functionality can be built upon that, and you can refactor code more often than not without destroying the functionality that relies upon it. Code is an infinitely more flexible medium.

The impulse to shelter your work from critical eyes is powerful, but "unsightly" work can be altered at the drop of a hat. Perhaps programmers need to be a little more open.

A counter example by Paul Graham from "Six Principles for Making New Things".

"Here it is: I like to find (a) simple solutions (b) to overlooked problems (c) that actually need to be solved, and (d) deliver them as informally as possible, (e) starting with a very crude version 1, then (f) iterating rapidly."

I think in our domain (software), there may be some additional rational to keeping things secret. An unpolished early revision of code may be a much better way to judge a job applicant than a resume. No one would consider publishing the rough draft of their resume.

The appropriate counter argument (IMHO), is that "unpolished" is different than "poorly written", and you generally don't want to work with managers that can't comprehend and appreciate the difference.