My mom waves and waves when we leave. Every time.
Just before we disappear out of sight, I look in the rearview mirror and she is in the distance, waving until the last moment. It is ridiculously inefficient, and there are so many more productive things she could be doing with those wasted seconds...and when you factor in the fact that it's not an occasional thing, it's an EVERYTIME thing, then those seconds turn into minutes and hours and probably days over the course of decades. The epitome of inefficiency; my suspicion has long been that she will never be asked to serve as the CEO of a Fortune 1000 company, and honestly, I think a lot of it has to do with her inability to be efficient with things like goodbyes.
I decided four years ago* I'm not interested in becoming somebody else's CEO either, and I am afraid she has infected a lot of people with her practices, which means I am surrounded by wastefulness.
And now I wave and wave to the end too. One of my favourite things I have ever learned from my mom, despite the great obstacle it became to my professional goals. Wave hard, wave long, wave til the end.