Stronger lats lead to better performance in nearly every exercise, the obvious being pull-ups and rows. But presses, deadlifts, squats, and even planks require strong lats.
Aside from acting as prime movers and stabilizers during many exercises, your lats also influence how your shoulders orient and affect your ability (or lack thereof) to reach a sound overhead position.
Spending a disproportionate amount of time building your lats can make them tight, shortened, and overactive. If this happens, your humerus can get pulled into a chronically internally-rotated position and make it difficult to achieve full shoulder flexion (reaching fully overhead). This is a recipe for disaster for shoulder health and posture.
One of the many ways to combat the risks is to statically stretch your lats. A common stretch is to grab an upright of a power rack with one arm and slightly squat and lean away from it.
It's a good stretch, but let's make it better. To get an even greater stretch, particularly into the lower portion of the lats, twist your body toward your arm.
Just open up your hip and let the knee of the same side you're stretching drop toward the ground. Give it a shot.