In professional photography, direct flash is often only used as the last measure. In other words, for a professional to shoot with direct flash, the available light is atrocious, there are no walls or low ceilings to bounce light from, or it's just pitch black. In these tough cases, direct flash is a lifesaver.
But if you're using direct flash, be sure you're conscious of the shadows the flash casts. Since the flash unit is a small light source, its shadows will be quite harsh. You can minimize them by paying attention to your background. Photographing someone in front of a white wall will produce distracting shadows. But move your subject as little as six feet from the same wall and the shadows will be much less visible as the wall will darken.
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