That's a good question. Short answer, I want a complete education, a job, and the ability to support myself. In the longer run, I hope to be remembered as someone who had an inpact on my field, and ideally as a person who helped my community/city/state/world at least as much as any "normal" person can. Along the way, a family would be great too.
But I also believe life must be worth it minute by minute and day by day. Why work 100 hr/week for 20 years just so you can vacation in Europe?
If you like Europe that much, MOVE THERE and teach English for a year or two! LOL.