What is one downside for consumers to competition in a free-enterprise system?

I believe the answer is: Consumers must be knowledgeable

Competition in the free market encourage producers to keep reducing the cost to make their products so it come up cheaper compared to competitors' products. This improve the chance of them using materials or methods that are dangerous for the consumers. Consumers need to be knowledgeable to distinguish the things hat might endanger us and which things are not.

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