There is always that risk. Google uses keyword matching to decide when to show your ads, and it does not always get it right. Broad match keywords, for example, can trigger ads for searches that have nothing to do with what you sell. Someone searching for something completely unrelated might still see your ad if Google thinks the intent is similar. This wastes money and brings in the wrong visitors. Checking your search term reports regularly and adding negative keywords helps reduce this problem. Have you ever noticed your budget draining from irrelevant clicks?