1) is secure,
1) scales well,
2) is robust and
3) meets auditing/compliance requirements.
How naive I was! An enterprise class application is one that
a) is deemed so by some buzzword-spouting salesperson representing a major vendor,
b) costs a lot of money,
c) uses every conceivable technology/design pattern the "architect" picked up at the latest dev confab he went to on company dime, and
d) crawls between its frequent breakdowns (so the support folks and on call people will have something to do)"