Why Is STB So Incompetent?

During the last summer holidays, a friend and I decided to go to S.E. Asia. Naturally we went to our friendly STB office to use the charter flights available.

It rapidly became apparent, however, that STB are almost incapable of organising their own flights, and absolutely incapable of organising any others. While it took a full month before out charter flights were confirmed, three months after booking we still had not heard about our regular flights.

Upon 'firing' STB, our bookings were made through Air NZ in a week, and we retained only one flight from Kuala Lumpur to Sydney with STB.

Having heard of STB inefficiency such things as having to ring STB twice weekly for three months to try and get a flight confirmed became matter of course. My question to STB is how the charter flight we did take was overbooked? At 11 pm., with the plane leaving in two hours, people with confirmed tickets were offloaded. What happened to these people? Why does the STB ticket have more 'ifs' 'buts' and 'maybes' than any other? Has this, or similar happened to anyone else?

Why is STB so incompetent?