Imagine you are playing with legos and you have a lot of them. You want to know how many legos you have so you start counting. You count "one, two, three, four, five..." but it's taking a lot of time and you get tired. Your friend comes in and asks how many legos you have. You respond "I've counted five legos." Your friend now knows you have at least five legos, but they don't know if you have more than that since you stopped counting.
This is similar to the idea of quantifier shift. It's when you change the order of a sentence to change how much information is being communicated. In the lego example, you originally said "I have counted five legos" which communicates the exact number you counted. But when you shifted the quantifier and said "I have at least five legos," you communicated that you have five legos or more.
Now let's look at a more complicated example. Original sentence: "All the dogs in the park bark." This means that every single dog in the park is barking. But when we shift the quantifier, it changes the meaning. "Some of the dogs in the park bark" means that there are at least one or more dogs barking, but not necessarily all of them.
Quantifier shift can be helpful when trying to clarify or simplify language. It's important to be aware of how the order of a sentence can change the meaning being communicated.