Strong players and pairs have worked their way thru complexed signal systems to be sure they give readable and clear signals to each other.
Sometimes this can do more harm than good. This was the case at this hand from a teamgame.
South ended up declaring 6♠ after a strong club bidding sequence where west had bid his diamonds a few times.
Looking at the north-south cards 6♠ is a contract you would like to bid. If west holds the king of heart you have an easy make, but there is also a shot with an endplay in clubs or diamonds where they have to lead from the king of hearts.
There was also another chance reached at the table, the discouraging signal!
West led the ace of diamonds, ruffed in dummy. East wanted to give partner a clear signal and followed with the ten!
This gave south an easy make. He continued with the king of spade, spade to the ace and the queen of diamonds to the king and ruff. Club to the king came next and the nine of diamonds to the jack and a ruff.
South next reached his hand by a club to the ace. Dummy discarded a club on the eight of diamonds and a heart was the only trick for the defense.