Most of my programming has been in various garbage collected languages, where indeed the language ensures that there's a path to use allocated memory, and if no

Most of my programming has been in various garbage collected languages, where indeed the language ensures that there's a path to use allocated memory, and if not, it gets rid of it. It doesn't stop you leaking memory though. You can store stuff in a map and then never get it out again, and depending on what you're doing, that sort of thing can be surprisingly common.