It's for an opponent to attack you from guard if you don't allow his to make effective connections to your legs and : Effective attacks in Jiu jitsu are predicated upon effective that form connection between you and an opponent. You can use that connection to control and attack. If you can't grip and connect – you can't attack. Now guard position has two major forms of grip. The is the more obvious one – your to your opponents body. The second is your FEET to your opponents body (usually the legs). Your feet do almost as much grilling as your hands in Jiu jitsu. When passing, if you can your opponents to grip you with his feet, then you have gone a long way towards shutting down his offense, and with his offense shut down, now you can focus on the stuff – passing his guard – without the distraction of being attacked as you try to pass. Seek to control his feet and prevent them making effective connections to your legs – your passing game will thank you