I've been using Linux and BSD for thirteen years and I can't even remember the last time I had to manually build and install an application from source (not counting random, early-stage hobby projects from github and things).
Open source Unix systems are the kings of package management. OS X pretty much does the exact opposite of 'package management', and any third party solution is based on existing Linux and BSD implementations.
Replying to this because I can't reply to the child comment.
This is something I keep hearing, and I keep linking to the same thing. "Download and One-Click Install" can easily be done on Linux. In fact, that's even what it is called: "One Click Install", at least as far as openSUSE is concerned.
Bonus: It still adds a repository so you have a working update path that plays nicely with the centralised package management that lets you manage every single package centrally, instead of having half a gazillion individual updaters, bundled libs etc.
"Package management" is the wrong term. OS X just makes installing software less terrifying.
Let's say you wanted to install Google Chrome. On OS X, you go to chrome.com and click the single "Download now" button, and it downloads.
On Linux, you get the same button, except clicking it takes you to another screen where you have to know whether you are a "Debian/Ubuntu" or a "Fedora/openSUSE" user or need a "community supported" version, and whether you want the 32 bit or 64 bit version, and whether you want to "add the Google repository to your system", and here's a thing to run on the command line if you don't want that.
The "sudo apt-get install yadayada" stuff is legitimately great for power users. But for most consumers, the OS X approach is definitely to be preferred.
Open source Unix systems are the kings of package management. OS X pretty much does the exact opposite of 'package management', and any third party solution is based on existing Linux and BSD implementations.