Genealogically speaking, the first of the month is super depressing.
Each month on the first the family tree displays a block of “Events on this day”… just like it does every other day of the year. On all those other days one may be enticed to learn a bit more about a marriage from the family history, or see a familiar name and wander off into memories, or be inspired to write down some half-forgotten story.
But twelve times a year you get reminded of all those events for which we only know the month it (probably?) happened, but not the precise day. For February there are 18, and each should be researched and settled.
January first is much worse.