I never understood this behaviour. I start up an app. I then go to the dock, right-click on the app and chose 'quit'. App in mac os x 10.7 no running shoe. The app icon stays on the dock. Then I right-click on the app again, and then choose 'options' and then choose 'remove from dock'. The the icon disappears. Why does the icon does not disappear when I 'quit' the app? For some apps this happens, for others it does not. What makes a certain app so special that it does not disappear when 'quit' the app and needs me to 'remove from dock'. I want that all app icons disappear from the dock when I quit the app. I never understood this.
Mojave adds a third section situated between app shortcuts on the left and your Trash along with other items on the right. This is where your recently opened apps are shown, provided they aren’t already included in the Dock. The new section in Mojave’s Dock lets you relaunch a recent app with a click. The Dock in macOS Mojave has a new, very helpful feature: It now displays recently-used apps. It’s handy when you’re going through a phase of using a particular app frequently, but you don’t. You can pin apps to it, and also launch them. Additionally, the apps that are pinned to the taskbar on Windows 10 can be opened with the Win+NumberKey shortcut. Something like this doesn’t exist on macOS out of the box but if you want to launch Dock apps with hotkeys, you can do so with a free app called Snap. Launch Dock apps with hotkeys.
MacBook Pro with Retina display, macOS Mojave (10.14) Mac shuts down on startup.
Apple's macOS Mojave added a feature called Recent Apps to your Dock — and it's not as useful as it sounds. According to Apple, the Dock will now show the last three apps you launched so that. To do so, either click on the Apple Menu at the upper-left corner of your screen, choose “System Preferences,” and then click on “Dock,” or right- or Control-click on one of those aforementioned.