be excessively optimistic, be realistic
This is a practice in which expectations about how much time will be expected to finish a future undertaking show a positive thinking inclination and belittle the time required.
This phenomenon happens paying little mind to the person's information that past undertakings of a comparative sort have taken more time to finish than by and large arranged. The predisposition just influences expectations about one's own undertakings; when outside onlookers foresee assignment consummation times, they demonstrate a negative inclination, overestimating the time required
