Why are applications still stealing focus?

Grrr, for about the 40th time today an application that was supposed to be doing something in the background stole focus.

In this latest instance, I was loading QuickBooks in the background while working with Outlook.  As soon as QuickBooks prompted for a password, the password window stole the focus from Outlook!

A while ago Microsoft added the feature to Windows that caused a background window to flash in the Taskbar when it needed attention, rather than stealing focus.  It’s been at least five years since that was first brought to market.  Why are there still applications out there that screw with the user experience, and why does Windows allow it?