Kanban Plugin for WordPress is groundbreaking because you pay it once and use for every project till the rest of your life on a website you make for your clients. They don't need to remember or book hundreds of different URLs, you just their own website domain :)
Also, it is WordPress! I use doznes of automations on my WP websites, I am familiar with WP ecosystem and now I can add one more tool to it and expand possibilities. Honestly, I didn't see it coming to WP...