First of all- welcome to the board and the profession.
From my understanding and you can certainly find out more information on the ANA website regarding statistics about this issue. www.nursingworld.org
The average age of a nurse is 45-47 years old. Nursing is physically demanding and I know that when I am 50-55 I only pray that I am not standing on my feet all day long, pulling and pushing. So nurses are leaving due to retirement issues.
Another source of the shortage is the lack of professors to teach nursing students. Many schools require Masters and Doctorate level degrees to teach, some a BSN will do. The problem lies that instructors are not getting compensated for their professional degrees that are expected of them. That along with state educational cut backs, classes can become larger with fewer teachers to teach. So like everything else in our society, the money is just not there. Until the Nursing reinvestment Act, which even then only gives 13,000 dollars to each SCHOOL in my state.
Another source of the shortage is that there is increased demand for nurses. Patients are much more acute and require more care. Nurses are not able to care for such acute patients and so hospitals sometimes try to lower patient nurse ratios by adding more nurses.
Yet, another source is that the physical, mental and financial burnout of being a nurse. It is very demanding and many nurses are leaving just due to the fact that other professions could offer more (insert money, benefits, better hours)... Nursing is a different profession than it was 100 years, 50, 25 and even 5 years ago. It has its benefits but to some, sometimes the disadvantages begin to outweigh the rewards.
The final source that I can think of is that as a nursing student, due to the lack of instructors, there is a HUGE waiting period to get into a program. Some people just lose interest in waiting 2-3 years sometimes getting into the nursing core classes.
If anyone else has anything to add...
Let me say that nursing is very individualized and rewarding to those who make it so. As much as it may sound that there is something wrong with nursing, there must be something right for all of us to be here.