As far back as World War 2, even the U.S. Government recognized the need for an alternative method to produce their training films that would captivate--and then inform and educate--their audiences.
The Armed Forces noticed that young soldiers were "falling asleep" during their training films--presentations that contained life-saving instructions about maintaining their weapons, not falling down on the job, even the importance of using insect netting to protect them from malaria-infested mosquitoes!
But it was too late, as their attention wandered with dry delivery of the spokespersons.
Wisely, they enlisted the services of Theodore "Ted" Geisel (that's the real name of Dr. Seuss, folks!) and Chuck Jones (later to be of Roadrunner fame) to come up with clever animated training films that amused (read "awakened") and then informed their audience. These films showed the wrong and often DISASTROUS results of ignoring good advice... something that animation can still do well today!
Sales and Training Videos, Infomercials
Why use animation for your sales and training videos, or your Infomercials?
Here Private SNAFU, while on military leave, blabs supposedly confidential information all over his home town. He might as well be painting it on a billboard while everyone listens... at one point, he even uses a plane to skywrite Army plans over the city...
Animation is ideal for showing worst-case (and best-case) scenarios and literal translations of themes, goals and ideas.
Furthermore, your audience is more likely to watch a cartoon in longer, more entertaining forms, whether on the web, or on a large monitor in a waiting room!