Here's why:
* Transform faults are primarily lateral. They are zones where tectonic plates slide past each other horizontally. This motion is different from the divergent motion at mid-ocean ridges where new crust is created.
* No magma upwelling. Unlike mid-ocean ridges, transform faults don't experience the upwelling of magma from the Earth's mantle that is needed to create new crust.
* Crust is offset, not created. The primary action at a transform fault is the offsetting of existing oceanic crust as the plates slide past each other.
Where is new oceanic crust formed?
New oceanic crust is formed at divergent plate boundaries, specifically at mid-ocean ridges. Here, the plates pull apart, allowing magma from the mantle to rise and solidify, creating new crust.
