If youre like most productive people, youre probably getting through several things on your to-do list, but not making progress on that one thing that you know is most important (and usually hardest).
Somehow that thing always gets left until later.
So it always seems like youre being "productive", but if youre distracted by a long list of priorities, are you being "effective"?
With "One & Done", the distraction of a long to-do list is gone. Theres only one thing, and thats the thing you know youve got to get done. Your top priority.