There are three type of karmas namely Prarabhda Karma, Sanchita Karma, and Agami.
Personality traits determine the quality of a person's actions or karmas which in turn lead to the consequences of the actions.
It is a series of five karmas or actions, which eliminate excess accumulation of doshas.
So every time we are about to reincarnate we look at our karmic balance sheet and decide just what karmas -good and bad-shall be reaped in the next life.