This idea that the left hand is bad is seen in many cultures. In fact, the word "sinister," for someone or something evil, comes from the Latin word for "left."
This man from Saipan explains how he is a lefty, but was corrected by his grandfather whenever he tried to eat with his left hand, even though his mother was a lefty and the grandfather let it go.
His way of getting back at his grandfather was to refuse to be the ring boy at his older sister's wedding when his grandfather asked him to take that role.
Some Words in the Video
Akaggue = left
Agapa' = right
Kånnai = hand
Bihu = grandfather (literally, "old man")
Båba = bad
Tailaye = evil
Masea Måno Fafayi-mo
Faye means "capable, skilled, proficient." Masea måno fafayi-mo means "whatever you are good at," meaning "do it how it's best for you."
This also includes the idea that you use your left hand if you're a lefty.