After talking with hundreds of current and retired professional athletes and surfing through hundreds of articles, here is our list of the top reasons that professional athletes go broke (in no particular order):
 
1) Lack of Visibility into Spending

2) Creating Entitlements

3) Risky Business Investments

4) Generosity

5) Legal Issues

6) Tax Issues

7) Alimony & Child Support

8) Spending it Twice

9) Misunderstanding of Financial Products

10) Substance Abuse

11) Misguided Entertainment

12) Abdication of Financial Oversight

13) Inexperienced Advisors

14) Career-Ending Injury