ok see if anyone has had this problem. and if you had what caused it?

my accord developed what sounded like an engine knock last night driving home from work. I tried it again today and it was still knocking, I popped the hood and looked to see that my #3 plug wire was not seated all the way down on the valve cover. I tried pushing down and it wouldnt budge, then I pulled it out and it clicked like the wire was fully seated. so I then pulled the valve cover off to find that my #3 spark plug somehow had come loose. i pulled it out, none of the threads were stripped or crossed so I put the plug back in tightened it down and its doing fine. so what caused the plug to come loose??

 

Is the 'crush washer' still on the plug?
Maybe it just wasn't tightened enough to start out with?
Find the Goober that installed it and slap him upside his head. LOL
Maybe there is a clockwise vortex in the cylinder under combustion conditions? That would turn the sparkplug counterclockwise and unscrew it.
It also could be, that little green men landed in their space ship and were checking out the engine.
Kidding aside, I've seen this before but have no real explaination why it happens; you just open the hood of the car and see a plug wire jumping up and down a little as the cylinder fires.

 

yea the crush washer was still on the pl;ug and intact, the threads were all fine. IM the goober that installed the plugs LOL. and yes thats pretty much what I saw the plug wire bouncing, not seated all the way on the valve cover and a knocking sound that made me think I was about to throw a rod.