There is a fundamental principle in lighting : the larger your light source, the softer your light.
Using any of the myriad of flash modifiers that are on offer, helps in achieving that - spreading the light from the on-camera Speedlight much wider, thereby creating softer light that direct flash would've given. However, (and this is a big however), these flash modifiers also throw light forward. Ultimately all flash modifiers do the same thing - they disperse a lot of light around the room, while throwing some measure of light directly Read more inside...