Is "giving your all" really a formula for success?

The advise, "Give it your all" seems on first hearing it like a reasonable demand for winning and being the best.  However, giving it all in any one area of life will quickly lead to imbalance and lots of failure in other important areas of life.  If I were to "give my all" to being good at financial management when would I have time to actually earn money?  Or if I were to "give my all" to my physical well being, when would I have time to spend with my family?  In the same way, giving my all at work or giving my all for my career only leads to imbalance in other areas of life.  At first, it seems so right.  But when did career become the most important thing?  Why is our job the one area of life were we can spend an inordinate amount of time and yet still have people's admiration and approval?  Work is just work and our jobs are just our jobs.  They will come and go, as will the title and the money.  I don't believe that giving my all means I have to give away my entire time to my career.  In fact, I think I can be very productive in a short period of time and free up even more time for those other areas of life that tend to get overlooked.

Have you noticed an imbalance when you have "given it your all" to one area of you life?