The messy middle
Google's model of how people actually decide between trigger and purchase: looping between exploration and evaluation, steered by heuristics like social proof, scarcity and authority, rather than descending a tidy funnel. The practical lesson is to be present and persuasive inside the loop, not to assume a linear path.
Where it's used
Used in media and CRO planning to think about comparison behaviour between trigger and purchase. Good for spotting where buyers loop and get stuck.
Example
Buying running shoes
Illustrative scenarioAn advert triggers the idea. You search "best running shoes", read reviews, drift to YouTube, forget for a week, get back to Reddit, compare two pairs, check whether a discount exists, and read what fellow runners say. Each loop is a chance to win or lose you, usually to a brand with better reviews or a stronger guarantee.
