गुरोः means teacher, preceptor as well as elderly person. Now since elders and teachers are human beings, they are bound to have some vices, imperfections. The vices of even a teacher or elderly person should be given up. In तैत्तिरीयउपनिषद् Guru rightly says to his disciple : "यानि अस्माकं सुचरितानि तानि एव सेवितव्यानि, नो इतराणि", Whatever is good in us should be accepted..