What a great quote by Hanon!
Here is the quote in its context. Notice the third to last paragraph. I love the irony that Hanon says, in essence, if you haven’t been practicing, you can play this book for “a few hours” and catch up. I’d love to tell my students, “Hmmm. It seems like you haven’t practiced this week. But good news: If you practice these exercises for three hours, you’ll be right back to where you were last week,”
Hanon – The Virtuoso Pianist Preface 1
Hanon – The Virtuoso Pianist Preface 2
Music Ed Lounge 
Really thankfull for sharing your amazingly thoughts with us Cymbal mutes .
Great thoughts. Mediocrity should not be endured at any level these days. We have a plethora of great performers and educators out there, and if we demand rigor in academic subjects we sure as heck need rigor (in a fun way) in music!