Comment by wongarsu
Aren't most licenses "not fully understood" in any reasonable legal sense? To my knowledge only the Artistic License and the GPL have seen the inside of a court room. And yet to this day nobody really knows how the GPL works with languages that don't follow C's model of a compile and a link step. And the boundaries of what's a derivative work in the GPL are still mostly set by convention, not a legal framework.
What makes us comfortable with the "traditional open source licenses" is that people have been using them for decades and nothing bad has happened. But that's mostly because breaking an open source license is rarely litigated against, not because we have some special knowledge of what those licenses mean and how to abide by that
Aren't most licenses "not fully understood" in any reasonable legal sense?
OK, fair enough. Pretend I said "not well understood" instead. The point is, the long-standing, well known licenses that have been around for decades are better understood that some random "I made up my own thing" license. And yes, some of that may be down to just norms and conventions, and yes, not all of these licenses have been tested in court. But I think most people would feel more comfortable using an OSI approved license, and are hesitant to foster the creation of even more licenses.
If nothing else, license proliferation is bad because of the combinatorics of understanding license compatibility issues. Every new license makes the number of permutations that much bigger, and creates more unknown situations.