Although it used to be an extremely sought after and glamorous job in which you're whisked to different locales on a daily basis, being a flight attendant seems to have lost some of its luster.
The airline industry in general changed drastically after Sept. 11, 2001. People became more hesitant to fly, and the people who continued to fly were subject to much more intrusive and extensive security measures, which made airports and airplanes a nuisance for many. Several airlines went bankrupt and most of the others slashed personnel in the face of declining revenue. That led to flight attendants having to deal with passenger fallout from increased fees for food, baggage and other amenities that used to be free.
Add to all of that a fairly high burnout rate and it's no wonder this stressful job landed in the top 10.