I don't think that salad bought in a store should have bugs and dirt on it, if you find them in your sink when you wash it you should change supermarket
EDIT: My bad, I was thinking about pre packaged salad, not like a whole head of lettuce, OP is correct and OOP should wash their lettuce better
Ah, you're right I was thinking about the pre packaged one, now all the people telling me they have found multiple bugs in their lettuce makes sense considering I would probably expect to find small bugs and dirt in a whole head of lettuce