A smooth product experience depends on what happens after the user clicks.
They send an action from your app, but behind that action there is still a path to
@solana that has to work properly.
The transaction needs to be forwarded, reach the right validator, and get included quickly enough for the action to still make sense.
That part is usually invisible to the user, but it has a direct impact on how fast and reliable your product feels.
Fast takes care of that backend path, so your app can focus on the experience while we focus on getting the transaction where it needs to go.
When the backend works well, the product simply feels better.