Good lighting is key to good photos. I usually turn off my flash and try to shoot with natural light. Although that isn't always possible. The above photo is taken with the flash on and no diffuser. Notice the washed out white on the Purina patch.
Exact same lighting situation except I put the diffuser over the flash. I will have to do a couple sample photos of people to show you the real benefit of this. So far I am thrilled.