NORTH AQ6 Q KJT5 AJ763 7 AJT864 A963 QT 432 7532 742 842   KJT985 K9 Q8 K95

Dealer: West    Vul: NS   MP Scoring West 1 Pass Pass North 2 3 Pass East Pass Pass Pass South 2 4

West played two rounds of hearts, declarer winning the 2nd in hand with the K.
Trumps were drawn ending in hand.
A possible losing club could have been discarded on a diamond to assure 5 tricks.
Given West had opened, North South had combined HCP of 17 in dummy and 12 for declarer, if East were to have the Q, then West would be left with at most 9 points for the 1 opening.

When West followed to the K with the T, discarding two diamond on the long clubs was a virtual certainty.