Answer:
Simulations are needed when the real life event is: to small to view, to large to view, rare or uncommon, or to quick or long to see in an efficient amount of time. Simulations are very useful when studying extremely long events and such. With a simulation you can control the duration of the event and can lengthen or shorten the amount of time to view the entire event within a timeline.
Hope this helps!
- Quinn <3