Sincerely? Because most suck for what I needed. I´m in the process of building a huge web, almost like a wikipedia, and there are flags everywhere. When I started looking for libraries I stumbled accross a few... but none was as complete as I wanted, or the sizes were all wrong or the whole thing was too heavy. You can see the comparison with any random flag. I needed something that worked decently in the developing countries and like a miracle in the first world. So this is more of a side project that grew all on its own.
When I started I did not know much about SVG, so I took the best library available and started making it better, and that was the size. But the beauty of SVG is that you can manipulate that easily :-).
This one is easy :-p, disable your ad-blocker. I have no ads anyway!
Well, actually there are 2 official ones: National Flags and Civil Flags. Most countries use the same but some others (Peru, Mexico, Spain, Dominican Republic...) use a diferent one that is usually less heavy. On the other hand, some flags are TOO heavy as they are, so I... boggled them down to something light to deliver, thus WF version was created.
I am on it, but only in my free time. But if you really need them, contact me and we´ll work something out.