I don't get it..

[Sir Upticious]

It is a joke from the same vein as this one:

A pirate with a peg leg, a hook for a hand, and an eye patch was
applying for a crew position. The first mate looked him up and down
and began to ask him questions. "How did ye lose yer leg?"

"A shark bit it off," the pirate replied.

"And yer hand, "the mate added. "How did you lose that?"

"A shark bit it off," the pirate replied.

"And... what about your eye?"

"I had an itch," the pirate replied.

"How could an itch cause you to lose yer eye?" the mate queried.

"I got the itch the day after after I got me hook," the pirate answered.