How do authors maintain a series quality and upload schedule?

I've been trying to start a series for a while, but everytime I've done so I kind of lose interest in whatever I was trying to communicate through it in the middle of making chapter 2.

At first I thought it was maybe an issue with how I write stories, mostly just off of vibes and shit that intrigues me, but when I tried using a more structured method I didn't even complete the first chapter.

I tried using AI to evaluate my works as well, asking it shit like 'is this a good phrase' or 'is this character arc impactful' but I think I just wanted praise. Didn't take long before I saw the detrimental effects It had on my stories.

That realisation stopped me from writing for a while, I've only recently started to get back into the groove again going with my 'off the vibes' style of writing. This time I actually know what I want to write about, and it actually really resonates with me.

So now I don't want to mess it up, I want to make the best story I can. I've been enjoying the free content on this sub for nearly 3 years, I wanna make something that can give people even half as much enjoyment as I received.