I don't know which story that you are trying to relate the writing prompt to, but I do agree with the prompt. I'll give an example from some fairly common stories that most students should recognize.
My first example story is The Outsiders by S.E. Hinton. Hinton waits to tell readers about Johnny's previous brush with the Socs until near the end of chapter two. She could have easily given the reader Johnny's backstory earlier in chapter one when she was introducing the rest of the Greaser gang. Instead, by delaying Johnny's flashback story, Hinton was able to extend and further build on the tension that exists between the Greasers and the Socs. Things just seem to be worse and worse for the Greasers.
Sometimes authors don't necessarily delay the telling of events. Sometimes authors leave them out completely in order to build tension. For example, Edgar Allen Poe's "The Cask of Amontillado" does this. He immediately tells the reader in the first paragraph that Fortunato has done something awful to Montresor and needs to be punished. The reader has no idea what that awful thing was, and the reader never finds out. But based on how the story proceeds, it must have been something awful.
One last example. Star Wars. The viewer goes through almost two entire films before learning that Vader is Luke's father. The viewer is introduced to Luke and Obi Wan right away, and we know that they are good guys. We also know beyond doubt that Vader is a bad guy and must be killed. That's how the first movie starts and ends. That's how Empire Strikes Back proceeds through all but the final ten minutes. That's when Vader pronounces the most famous words in the movie franchise. "I am your father." Those words hit the viewer like a nuclear bomb, and the tension builds exponentially, because now everything that we once thought about Vader needs to be re-examined.