I saw a similar thread but it was over 5 years old, so I'm making a new one. I thought it could be fun to share braindead moments you've had as it relates to pins.

Mine from last night: I was rebuilding my flippers on my T2 (thanks, Vid!). I got everything put back together and was testing them out, when a screw fell down the playfield and into the bumper. Ooops, where's that from? I couldn't reach it with my fingers, so I went into my tool bag, grabbed the magnet-on-a-stick tool, and got the screw. After reviewing the playfield trying to find where the screw was from, I put the screw aside and started playing T2 again to make sure it worked.

But then things started getting really screwy. Two balls would eject into the shooter lane. The game was randomly lighting things up, gave me an extra ball, and was just generally extremely weird. I thought for sure I screwed something up, somehow, even though I couldn't think of why a flipper rebuild would cause all of these issues.

Then I got a multiball. And saw four balls flying around. What?! There's only supposed to be 3 balls in the machine, where did the 4th one come from?! How would I accidentally have put an extra ball in?

After literally five minutes of racking my brain, it hit me -- the magnet tool had a ball stuck to it. I took the ball off, grabbed the screw, put the screw aside, and since there was a ball in my hand, I just put it in the machine without thinking. Whoops! Now I know what happens when you have an extra ball though. Boneheaded, but at least no long term ramifications.

And I never did find out where that screw was supposed to go....