How is magnitude of any row as well as column of a rotational matrix is equal to zero?

Any column in rotation matrix represents a vector i, j, or k of frame 1 in frame 0. But how is the magnitude equal to zero? But how is the magnitude of each row equal to one? And also how is magnitude of a row equal to zero?

If possible, please use simple language and I don't have deep knowledge in this sector.

edit1: meant to write magnitude of row and column = 1 but wrote 0.