Comment by jokoon

What I mean is that the game design is poorly made, unbalanced. Only vanilla and space age seems like they're accessible games.

Generally game design revolves the concept of a effort-reward loop: the player must feel he is regularly advancing in the game, at a steady pace, with a difficulty that slowly increases.

Mods are often badly designed because they are made by hardcore factorio fans who don't understand this or follow this golden rule.

There was a FFF who talked about a game designer they hired, and wube constantly had to make his designs simpler so the game can be a success. It requires a lot of work.

Making a great game is about "easy to learn, hard to master". A lot of people don't understand it, but a game must be attractive enough for casual to medium players, or it just will not sell.

The magic of factorio vanilla and space age is that the difficulty is well designed. Mods often just don't follow that rule, or have a lower quality.

There is more psychology behind game design that we want to admit.