Why don't many PCB's include the LED resistor?

[powerplayj]

This is by no means a rant as I am at the mercy and in debted to all the good layouts provided on this and other sites.  I was just curious why many folks don't include the current limiting LED resistor on the actual PCB?  It's such a pain to wire and shield sometimes and it seems like this would be an easy option to include on the board.  In the meantime, I'm sure it wouldn't be too hard for me to do this on MSPaint. 

[John Lyons]

They problaby don't include it because there are different ways to implement bypass switching and it depends on whether you use a LED or not. Simplicity sake as well. I usndertand your question though. It would be easier to have it on the board...