Read the table.
Leave room for doubt.

Visible groups can narrow possibilities. They rarely reveal one certain hand. The useful skill is turning what is public into better questions—not acting as though you can see through tiles.

See

State the exposure exactly.

Tile type, group size, suit, jokers, and what has already been discarded.

Compare

Build a small range.

Keep multiple compatible possibilities alive until later evidence truly removes one.

Choose

Compare risks late.

Ask what is accounted for, who could still use a tile, and what keeping it costs your own hand.

A called discard is information—not retroactive proof that you should have known.