Do you mean the lengh of episodes or the number of episodes?
About the lengh of episodes:
If the episode is too long (30+ minutes), then I wouldn’t read it, unless it’s engaging and fits the story. My first story has short chapters (3-5 minutes reading time) because I was a beginner, and I couldn’t estimate the reading time very well back then. I received a lot of criticism because of the short episodes. Interestingly, it looks different in my second and current story. The episodes are much longer. If you are a quick reader, it will take you approximately 20-25 minutes for each episode, and so far, no one has complained about the length of the episodes.
About the number of episodes:
It all depends on the story itself, and by that, I mean the content.
For example, you read a murder mystery and, after 20 episodes, you find out who the killer is and successfully arrest him. The story should be over, right? But not for some authors. They write ten more episodes that have nothing to do with the murder mystery. Instead, they write about the unplanned pregnancy of the MC that came out of nowhere. The next 10 chapters are about her pregnancy, although the main plot has ended already.
I know it’s an absurd example, but what I’m trying to say is that when the main plot ends, the story should end too. And believe me, it’s better this way. It doesn’t matter whether the story only has 10 chapters or 40 chapters. As long as you, as an author, limit yourself to the most relevant points of your plot, you won’t write “unnecessary” scenes. I’m okay with prologues but don’t drag it out, and usually, a prologue is one episode long and not more.