My motivation encompasses several reasons. No particular order....
1. Hopefully not to live paycheck to paycheck anymore.
2. A potential (future) job promotion (and the income that comes with it).
3. Personal satisfaction of knowing I did something that not many people around me have accomplished.
4. Provide my family with a little better standard of living (not that its bad, but you know).
5. Job security.
6. Getting "back to even" with some of my friends that are engineers and making more $$.
7. Being able to tell people I'm a "Professional Engineer" (or just engineer) and not a technician when they ask about my career (not that a technician is bad).
8. Seeing my name with a P.E. behind it!
Another note I'll add...Fall 2010 will be my second time taking the EE-Electronics test (after failing last April). I've found studying this time around has been easier because I remembered many of basic concepts I had to "re-learn" the first time. So I'm able to spend more time on the meat of the subject instead of the math I forgot. I feel more confident in my studying (even though my personal life lately has curtailed it a bit). Plus my trial run in April helped me to know what to expect on the test this time around.
My two cents...