Community viewed as a cluster of grapes from which every now and then a rotten one must be plucked and discarded. It is, by far, the easiest course of action, and there is plenty of reinforcement. Our culture puts a premium on the slick and convenient, and conflict is inefficient and messy, to say nothing of hard work. According to Jesus, people and our relationships with them are far too important to simply let go. Wounds are worth healing.
Ruptures are worth mending.
People are worth reclaiming, even though it well may be the hardest work there is. It isn't a novel thought in scripture. These instructions for seeking reconciliation, for example, come immediately after Jesus has compared God's seeking love to the shepherd who leaves the 99 sheep herded together in order to go out and find the one who has strayed away. And immediately after these verses in Matthew's gospel appears Peter's question about how many times he should forgive someone who sins against him. The unmistakable message is that Christians don't quickly or easily give up on each other.