Everyone just turns up to this kind of meeting for the sake of being counted.
Tips
history
卯 (mǎo) is the 5–7am slot in the twelve earthly branches — the hour when imperial yamens held morning attendance. 点卯 literally means 'to mark the mǎo hour'; an absent official got a missing dot beside their name.
register
Modern usage is colloquial and slightly cynical: showing up only to be recorded as present, with no real engagement. Often in 点个卯 (diǎn ge mǎo) with the verb-measure 'do a quick roll-call appearance'.
