I somewhat disagree. Yes, if the GUI has five possible actions and you're only familiar with one of them, it's much easier to learn to do the other four things

I somewhat disagree. Yes, if the GUI has five possible actions and you're only familiar with one of them, it's much easier to learn to do the other four things with the GUI. But it's tedious to do something the GUI wasn't designed for. Once the GUI reaches hundreds of actions it's no longer easy to find the functionality you're looking for.