Flying blind versus flying by instruments
A website without analytics is like flying a plane with the windows painted over. You can feel that you're moving, but you have no idea where you are, how fast you're going, or whether you're headed for the destination. Analytics integration installs the instruments — turning a silent website into one that reports on exactly what's happening.
The value isn't the data itself; it's the decisions the data enables. Should you invest more in that blog? Is the new homepage actually working? Why did leads drop last month? Without analytics, these are debates settled by whoever argues loudest. With analytics, they're settled by evidence.