Explosions, flashy transitions, and dramatic zooms grab attention for a second. A story holds it. Viewers remember a problem they recognize, a character they like, and a moment that makes them laugh, not the effect in the background. Effects are also expensive: Simulmedia lists special effects at $10,000 to $100,000 or more in a TV production budget (Simulmedia).
Short commercials leave no room for filler. Most video marketers (71%) say videos between 30 seconds and 2 minutes are most effective (Wyzowl), so every second needs to move the story toward your call to action. Effects should support the story, not replace it.