Also OK to have a life goal to retire with 40.
But then clearly draw the line, discuss it with your employers and don't make a go-slow as undocumented feature of your daily life.
Bad for Karma :-)
I know a few friends who with 40 said that too much in-house is too much for them to be motivated and going freelancer or consultant is too much. So they made a deal with their employee that they work 50% from age 40 onwards and for the other 50% they are free to:
a) sleep in the afternoon and go to the Coffee Corner in the evening
b) be motivated to do what they have always wanted to do without any risk
In 10... no... 5 years time... I would like to return to this thread and see how the current 25 year olds feel when they are 30 or 35. Of course the 7 year olds and the 70 year olds can also be smart and have stayed young. Doing funky innovative things.
Cheers,
Julius
ps: If you are aiming for the world chess championship "points" then starting early counts more than becoming 40 years old as you have no chance if you did not start early to learn.