fusionlingdraws

I think a lot of people misunderstand future vision because they don't understand what it actually is.

A well known "theory" that's basically accepted as fanon by many SU fans is that Gems are computers.

From that perspective, we can look at future vision as a simulation of possible futures based on predictable behavior.

The reason Sapphire and Garnet's future vision is often wrong is because of miscalculations in their simulations; things they did not factor in or account for in their predictions.

Sapphires on Homeworld were likely mostly accurate because Gems were expected to behave in predictable ways, and most did exactly what they were made for and exactly what they were told.

The only time a Sapphire on Homeworld would be wrong is if a Gem or organic creature did something unexpected or against Homeworld rules, laws, or sensibilities.

This is why Garnet struggles and constantly works at improving her future vision by improving her understanding of the people around her and how they change and grow.

But of course Steven also reminds her that she's allowed to make her own future and steer the ship in a direction she wants, without worrying so much about the next surprise.