Communities on big instances have a chance to grow. So once it gets big enough on something like world, they could put up a movement post and switch the community onto a smaller server. I have a lemmy ml community but it only has 227 subs so its currently not worth moving. There are enough subscribers that some posts get upvoted and end up like with 25 upvotes in a hurry so they appear on the tops lists. Obviously, the more the community hits the top lists, the more people will see it and maybe subscribe to it.
Communities on big instances have a chance to grow. So once it gets big enough on something like world, they could put up a movement post and switch the community onto a smaller server. I have a lemmy ml community but it only has 227 subs so its currently not worth moving. There are enough subscribers that some posts get upvoted and end up like with 25 upvotes in a hurry so they appear on the tops lists. Obviously, the more the community hits the top lists, the more people will see it and maybe subscribe to it.