The ingredient added last can still change everything already in the pot.

Nothing is settled just because most of it is done. A small thing put in at the end can reach every part of what came before, changing the whole rather than sitting on top of it, and that works for good and for ill. A late remark can recolour an entire conversation; a late correction can rescue an entire project. Lateness is not the same as irrelevance.

Something you have been holding back because it feels too late to raise is worth weighing again. The near-finished state of a thing is not a reason for silence. Say it while it can still be stirred in.