One to open the box... three to declare it wasn't single... one to screw it in...four to say it was the best bulb ever encountered and 6 to shout "clique" when it's switched on..
"A single changes it and the couple watching say that's not a true bulb change unless another couple join in "
one to hold the socket, one to finger it to find out whether they got the right fit, then another one tries and confirms this, several then try to ram the bulb home, completely missing the point of contact, until the right connection is made, the current surges and the bulb lights up and promptly explodes...and repeat as necessary..
One to pull it out and push it in again, one to switch and send juice coursing through it, one to stand close by and wank while they watch, one to moan that he's not getting any responses to his messages and they all need to verify the bulb after.