It's like "why won't Pizza Hut give me my food".
Because there are no workers on staff.
You may place an order for a pizza online but that doesn't mean a darn thing of there's nobody there to make it. Same with seeds and seeders.
Now if you're talking about your own torrents not seeding, that's because there is nobody downloading it for you to give them data. In this case you are the Pizza Hut and you are the Pizza Hut workers. You're making pizza but nobody is coming to get it. That's because nobody placed an order in the first place. If the seeding bar is red then that means you need to update your trackers. In this case it's updating the phone number to your Pizza Hut. Now people can call and connect to you to order a Pizza AND pick it up.