The usual marathons, the popular ones, are done in a group.
They have a start time.
A finish line.
A way to qualify.
A route.
A crowd.
And a date announced a year in advance.
Mostly, they have excitement, energy and peer pressure.
The other kind of marathon is one that anyone can run, any day of the year. Put on your sneakers, run out the door and come back 26 miles later. These are rare.
Its worth noting that much of what we do in creating a project, launching a business or developing a career is a lot closer to the second kind of marathon.
No wonder its so difficult.