The Gemara records that various Amoraim cried when they read certain verses, and some of those verses indicated that even if one repents from his misdeeds and has exemplary character traits, there is a only a possibility that HaShem will show favor to the person.
It is noteworthy that in the recital of Slichos we beseech HaShem with the words אולי יחוס עם עני ואביון אולי ירחם, perhaps He will have compassion on a nation that is poor and impoverished, perhaps He will have mercy. We can suggest that we specifically implore HaShem with these words as we are acknowledging that our lives are in the balance and we are not entitled to anything. Rather, we express our hope that HaShem will have compassion on us and grant us life and fulfill our requests.