Review One of the reasons Linux has never caught on as a desktop operating system, as Linux fans know, is that Linux isn't a desktop operating system, it's a kernel. And assembling it into a coherent package users can install is the job of a distribution.
This is a very different distribution model than the one Apple or Microsoft uses, and it confuses newcomers. Windows and macOS are easier to understand, they are single things made by single companies. Canonical and Red Hat notwithstanding, Linux is not packaged and presented this way at all. I've long believed that this difference is one of the key stumbling blocks to wider Linux adoption.
Apple has macOS, Microsoft has Windows, Linux has... hundreds of awkward, confusingly named options.