The Chasidim have a very beautiful interpretation of the passage , "God remembers what men forget."
They say that if men only recall their merits and forget their sins, God only recalls the sins.
But if men only remember their sins, God only takes their merits into account.
Nevertheless, remembrance and forgetting are not really antithetical.
Both are recollections and are linked in subtle ways.
The first day of Rosh Hashanah can be seen as a day when we obliterate the previous year.
It is a time of transition.
The second day of Rosh Hashanah starts the New Year.
–Rabbi Adin Steinsaltz
From The Seven Lights by Rabbi Adin Steinsaltz