Why can you read INRI over the crucifix?

In religious images, particularly among Catholics, the word INRI can be seen written on a piece of wood above the crucified Jesus. The inscription INRI stands for "Iesus Nazarenus Rex Iudaeorum", which means "Jesus of Nazareth, King of the Jews". It was written and placed by Pilate, according to the Gospel.

Knowledge + Why?