@media_dept
More often than not, there's one if not several somebodies that will create .deb packages in a PPA, which will only require you DL the package and run it. If you want to make it an updateable package, then you can use CLI to add the PPA to your sources list.

For ex, with the laptop I just got, I installed Mint which is Debian based via Ubuntu. I'm going to use it for fixing electronics, which means I'll need to install several bits of software to help with that. One of those would be Open Boardview, which is an app that uses certain file types to display an interactive PCB, so you can click on a component and see details about it, and what it's connected to on the board. From the site for the program it's just a zip with a .run file. I searched for Open Boardview .deb and found a package I could just DL and then click on to install. Have to be a little careful with this method as there's always a chance you get something extra with the software you want tho.

The reason this is even available is most distros are pretty slow at approving software. So if you go look at a program from the distro and compare it to the current version from the Git or wherever it's hosted, often you'll find the distro is at least one version behind, if not several. They do this because "stability", which is understandable, but it means you'll be missing current functionality and bug fixes if you only rely on the distro versions.

It's up to the user, of course. If one isn't comfortable getting software from unofficial sources, that's understandable. I've been using Linux for nearly 2 decades now and pretty early on I realized I had to use unofficial stuff just to get things I wanted to use to work. One of these days I'll have to tell you about figuring out how to run World of Warcraft in 2007 on Ubuntu via Wine, lol.