Why did nelson Mandela change his original name?

Answer 1

he went to school which is where he got his English name "nelson" because his teacher had difficulty pronouncing Rolihlahla

Answer 2

Nelson Mandela's original name was Rolihlahla, which means "pulling a branch off a tree" or "troublemaker" in Xhosa. He was given the name Nelson by a teacher on his first day of school as part of a British tradition to give African students English names. Mandela later embraced his new name and used it throughout his life.