After G‑d taught Moses the procedures for ascent-offerings and peace-promoting-offerings, He taught him the procedures for sin-offerings. These sacrifices atoned principally for unintentional misdeeds.
Unintentional Misdeeds
נֶפֶשׁ כִּי תֶחֱטָא בִשְׁגָגָה וגו': (ויקרא ד:ב)
[G‑d told Moses,] “If a person unintentionally transgresses.” Leviticus 4:2

The reason why sacrifices were offered for unintentional misdeeds is because our deepest interests and aspirations, as well as our most intimate cares and concerns, are revealed specifically by our impulsive actions. It is through these actions that our “subconscious” self involuntarily surfaces. We do not need to atone for the misdeed itself, since it was done unintentionally. What we need to atone for is all the previous conduct and laxity that molded our inner selves into someone whose interests run contrary to G‑d’s will and who spontaneously rejected it.

In this light, our unintentional misdeeds warrant greater atonement than our intentional ones, for unintentional deeds indicate that we have a deep, subconscious attachment to a type of behavior that is contrary to G‑d’s will. Intentional misdeeds do not necessarily indicate that we suffer from this hidden flaw.1