I thought about this question when I read an interesting comment by @Simon Fitch in [his answer][1].

In the complementary amplifier stage, in total there are three "pulling" elements - Q2 is a "pull-down" transistor when Vin is negative, Q1 is a "pull-up" transistor when Vin is positive, and the load RL is constantly a "pull-middle" resistor :-)

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![schematic](https://i.sstatic.net/UR79E.png)

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[![Push-pull graph][2]][2]

However, for some reason, this configuration is called "push-pull" stage. So there should also be a "pushing" element.

My question is, "What is it?"


  [1]: https://electronics.stackexchange.com/a/663830/61398
  [2]: https://i.sstatic.net/mmYAw.png