For marathon runners, cyclists and anyone who enjoys endurance sports, your VO2 max can be an important predictor of your performance, because it’s your aerobic capacity. Other factors including your running economy and your efficiency are important too.
But if you’re a football player, or a rugby player like I am, it’s particularly important to have an endurance base. You might have to sprint after a ball every now and then, but having a good VO2 max is going to give you the capacity to keep going for a long time.