I like macOS's window management in general but this is a good point. The dot indicators on the dock tell you whether an application is running, which on macOS

I like macOS's window management in general but this is a good point. The dot indicators on the dock tell you whether an application is running, which on macOS doesn't necessarily mean it has any windows open. Clicking a dock icon results in a different action based on whether the application does have open windows, which is not visually indicated.