Filament Winding is not an easy process as 3T fiber is dry (not yet sticky with resin, see below), it doesn’t want to stay on the core very easily.
Therefore, to simplify and speed up this process, it was decided to use the resin bath. Here the fiber runs through the resin before being spun onto the core.
With pre-impregnated carbon, you have to place the pre-formed frame into a cold mold. Otherwise, the resin starts to react as it hits the mold, before you’ve finished placing the whole frame.
When you use dry fiber, you can stick it into a hot mold and nothing happens. Then you close the mold and inject the resin, at which point the resin starts the curing process. So you can produce frame after frame without having to cool down the mold and heat it up again.