Boarding Time

I am always puzzled with airplane boarding times. On each step of a way you are warned that this is essential for timing. Then you come to the gate and wait. And wait.

Since this delay happens so often, one could expect airliners to move boarding time a little. But, of course, boarding time for aircraft with 50 seats and for one with 100 is completely the same.

In this era of computers, is it so hard to check old boarding data and optimize process a little?

P.S. Here I must note one single exception - Malév. That Hungarian airliner is always boarding on time. Why other cannot do the same?