You know how people tell you to find a partner to go jogging with instead of going by yourself?
It’s actually really solid advice, and it can be applied to a lot of things. And even if you say “don’t worry, I’m already motivated” or “I can motivate myself” it’s still a good idea to find someone, or a group of people even, that share a goal similar to yours. It helps if you’ve got peers to compare yourself to or ask advice of, and being able to help others out can also be rather satisfying.
I think this is why communities that focus on one specific thing exclusively are so great and tend to thrive in their niches… as long as they don’t start hosting too many people. It needs to keep that personal touch to it, you need to be able to recognize faces and say “oh yeah he’s that guy who is working on that thing”. Approximately a hundred people max, maybe? Assuming they aren’t all the busiest of bees.
Bottom line: join communities that do what you do. It’s fun and comfy and can help you stay motivated!