In art there is something called the serendipitous mistake.

One of the reasons traditional artists hesitate about working in a digital format is that you have the ability to undo anything you don’t like.  You’re not forced to work around it.  You don’t have to think outside of the box to come up with something clever.  In a traditional piece of artwork, you have to work with what you got, warts and all.  That constraint can push a piece of art or illustration or animation to new levels.  When I first started in the industry, I worked with artists who deliberately introduced serendipitous mistakes.  They restricted the undo stack to 1 action, they did all of their under-painting on top of an upside down photograph or a text created from paint splotches on the floor.

That serendipitous mistake effect carries over into game design as well.  Whenever you work with a team there are going to be design issues.  Sometimes they stem from mis-communications between team members, sometimes they are constraints with the hardware or the software.  Design inherently forces the serendipitous mistake, so keep your eyes peeled and be ready to embrace it when it happens.

I ran across this interesting paper tearing down this type of effect here:

Maximising_Serendipity_The_art_of_recognising_and_fostering_potential