There is yet another milestone approaching as I'm closing my 500th post in 200wad/cowriters. It's always nice to have such things to look forward, but they also have a negative effect.
Writing daily without worrying any upcoming milestones is relieving. There is always only that one post to write about and then I'm done. But when there is a round number of posts or such approaching there is always the period when it's close enough to be meaningful. During that time it's not just writing that one post. It's just one less post to write in the remaining amount until I cross the line. It can feel overwhelming.
Another issue is the anxiety of failing so close to something remarkable. It would be a shame to fail at 499 posts for example. When I don't care about such things there is no pressure. I just do it. Closer I get the more nervous I become. O don't want to fail.
Despite them being nice once reached I'm happy there isn't actually that many of those anymore at my post count. Another month or a hundred post isn't that remarkable anymore. A year, 500 posts, those still mean something. But even them fade soon enough. It's only the first couple of every order of magnitude that counts.