I only chose teams to put on the website that really use it regularly. We have a bunch more logos of the type others here describe that I could have chosen but that's dumb.
But the actual answer to your question of how is that it took a long time to build something they wanted to use. We've been building a version of Grain for about 15 months now, about 6 months on the product we just released and 9 months on a version we threw away.
Eventually we built up word or mouth of happy users that refer other teams. It's a grind to get real teams to adopt anything but it is possible with continued effort.