Our Gemara on Amud Beis describes the aspects of particular ligaments in an animal’s leg, and to what degree they can be damaged but still not render the animal a tereifa:

“With regard to the removal of the convergence of sinews in the thigh, which renders the animal a tereifa, Ameimar says in the name of Rav Zevid: There are three strands, i.e., sinews; one is thick and the other two are thin. …Mar bar Rav Ashi teaches a lenient version of this ruling: If the thick sinew was severed, since there is a majority of the number of sinews that remains, the animal is not a tereifa. Likewise, if the thin ones were severed, since there is a majority of the structure that remains intact, the animal is not a tereifa.”

Toldos Yaakov Yosef (Pinchas 43) sees this true in a spiritual dimension as well. When it comes to evaluating a person’s merits and deeds, there can be two methods of counting. We can count the raw number of deeds or sins, or we can consider the severity or weight of the sins. Toldos Yaakov Yosef says Hashem counts either method in the direction of merit. If the majority of his deeds are mitzvos, he is judged favorably, even if his sins outweigh them due to their severity. However, the opposite is true as well. If a person had numerous sins but the value of a few small mitzvos outweighs them, then too, he is judged favorably.

Toldos Yaakov Yosef shows this process as evident when the Torah describes Hashem’s judging Sodom. The verse states (Bereishis 18:20): “The outcries from Sodom and Gomorrah are numerous, and their sins heavy.” We see that Hashem was looking to find either a majority of good deeds or even a significant few good deeds that could change Sodom’s judgment. Alas, in neither category were they worthy of redemption.