1. Strong Business Analyst skills (Soft tech: interacting with users; understand the business processes and logic)
2. Strong Analyzing skills (large stamina to look at numbers all day; week-after-week; note: very few people can do this even amongs CSCI majors).
3. Strong Technical skills (Hard tech: SQL Server, DBA, Data Warehouse/Mart, cubes).
You can't analyze what you don't understand. You have to be as good or better about the business process and logic than business users. This requires heavy interaction with customers. You can learn technical skills at school, self-teach, training, etc. but you only learn the details of a company while you work. Sure you can learn the basic flow of healtcare or insurance but even in the same industry, alot of business process are unique to that company. In essence, that is what makes a BIA essential. Strong knowledge of business and technology. And technology can be learned outside the company and can be easily replaced.