Question from title, removed now
A lot of the appeal of LPs does come down to personal preference of the viewer and LPer but it also helps if there’s some sort of general idea of what the LP wants to be. Whether it’s a casual and chill runthough you can listen to on the side, an in-depth look at a game, or anything else that can pop up, it helps focus on what the LP is about and can potentially garner interest in it.
The way I put it is that the question “Why would people want to watch this video?” is something you have to answer for yourself in order to make the video. I try to focus on games that I think most people won’t be familiar with, so that my answer can be “Because they want to see a game they otherwise wouldn’t know about.” Sometimes I play really bad games, and then my answer is “So that people can experience the game without having to play it for themselves.” Sometimes I play really good games, and then it’s “So that people can see how good the game is and hopefully get a copy.” Most of the success on Youtube seems to come from alternate answers, like “Purely for the personalities of the people playing, regardless of what game they’re playing,” or “To see an expert performance of a difficult game,” or even just “To get a full walkthrough so they can see how to play better.” There are plenty of niches you can fit into.
And there’s always the universal answer if you can’t come up with anything better. Why would anyone watch your videos? “Because they’re there.” It’s not as likely to draw a huge audience, but if you’re making Let’s Plays because you want to, and you enjoy doing it, then the audience is a secondary concern. If you don’t enjoy making them, then it’s probably best not to.