Originally Posted by FBinNY

Looking for drivers to anticipate them opening doors is difficult and unreliable. However, folks opening doors isn't a random thing whereby they sit around then open the door at random.

So a helpful technique is to keep a weather eye well ahead down the road for cars parking. Those newly parked cars are the ones that will have a driver or passenger exiting momentarily. Of course, this isn't bulletproof, since someone may park, and sit around getting stuff together before exiting. However, it's another tool which can be helpful in predicting open doors before they open.