Let's say our function did something right where you would have expected to have a maximum value. Let's say the function is not defined. And right where you would have expected to have a minimum value, the function is not defined. And so right over here, you could say, well, look. The function is clearly approaching. As x approaches this value right over here, the function is clearly approaching this limit. But that limit can't be the maximum value because the function never gets to that.