Because he never pays his debts.
or
Because he was under cover.
or
50. One to screw in the light bulb and the remaining 49 to guard him .
or
6: 2 to screw in the bulb and 4 to testify that it was lit from the moment they began screwing.
or
Neither, they all burn shorter.
or
A snail because it carries it's home.
or