Such is life

I for some reason can not seem to be the person that I expect my children to be.  I have my son do his homework every night and make it a point to show him how important it is for his life.  Do I do this for my life and my future?  Of course not I have been the biggest slacker and procrastinator I know.  I have not been reading, studing and just getting the C instead of working for the A.  What is it that we have done to ourselves that we expect excellence from our children but show them that we do not work for excellence.