[rstuart4133]

As others are said Debian developers aren't paid, by Debian at least.

Many of us use Debian in our day jobs. I used to Windows at first because there was very little else, ran away to RedHat when it became clear it's very hard to develop something reliable on a base that is a black box and so unreliable and had abysmal support, ran away from RedHat to Debian at about the time of the Fedora / RedHat enterprise split because they pushed a minor update with so many incompatibilities it broke my systems.

In Debian I found a whole pile of like minded sysadmins/system builders working collaboratively on distro they can use in their day jobs. What do you need as a sysadmin - a rock solid base. Debian moves slowly, is tested for over a year prior to release, backports security patches to stable instead of moving to a new version, has hundreds if not thousands of rules and tools to enforce quality standards, and discussions with its users (who are also the developers) that span weeks if not months over technical changes to ensure they don't break things. The flips side of this coin is you will see people complaining about how old Debian is, or how hard Debian packaging is. All true. And it's that way because it's the only way we've found to create the distro these sysadmin/system builders can build on and trust. It's not a coincidence Debian lead the world into reproducible builds.

In answer to your question "why do they do it", the answer is because we haven't found a better way. Ubuntu's constant introduction home grown features like MIR, their desktop, and the snap store are designed to benefit them, but it's users. Proprietary systems are out of the question now in many places - hidden code with hidden bugs controlled by hidden entities and state actors isn't we or many of our employers can tolerate. What other way is there? It seems to me that open source (which is what Debian is - an open source distro), it the only way to build these types of systems.