Which Card is a Loser in my Dummy?

The contract is 3NT. The opening lead is the 4♥.

Dummy
♠AKJT5
♥
♦KQT83
♣AQJ

Declarer
♠Q8
♥QJ32
♦AJ7
♣8642

There will be time to reflect on why my Partner and I are not in 6♦ later on. Right now I have to do the best I can do in this contract!

What do I do first? I count my winners in a trump contract. Tricks I will get without losing a trick in the suit first.

♠5 winners
♥0 winners
♦5 winners
♣1 winner

That's 11 winners. I should do fine.

The opponents are leading a ♥ and they will probably take the first 2 ♥ tricks. That means that right away I have to throw two cards away from Dummy. What ones should I throw away?

Obviously I want to throw away losers. Keep my winners. That makes sense. Which cards are my losers?

Without thinking about it I might throw away the two lowest cards from Dummy. So probably the 5♠ first and then the 3♦ next. Low cards are losers right?

Wrong. That ♠ trick was a winner remember? So was that ♦. I just threw away two winners from my Dummy.

Which two cards should I have thrown away? The only two cards in Dummy that are not winners are the Q♣ and the J♣.

So when my LHO leads a ♥ I will throw away the J♣. It is useless. Now my RHO wins the A♥ (I play low) and returns the 8♥. I play my Q♥ and my LHO wins the K♥. Now I throw away the Q♣ from Dummy. Another useless card. This is what I have now:

Dummy
♠AKJT5
♥
♦KQT83
♣A

Declarer
♠Q8
♥J3 -- this J is good now. The AK and Q are all out
♦AJ7
♣8642

I should be able to take ALL the rest of the tricks. I just have to remember to play HIGH cards from the SHORT side first to avoid blocking any suits.

What would have happened if I threw away a low ♠ and a low ♦?

You would have come down to this:

Dummy
♠AKJT
♥
♦KQT8
♣AQJ

Declarer
♠Q8
♥J3
♦AJ7
♣8642

How many winners do you have now?

♠4 winners
♥1 winner
♦4 winners
♣1 winner

That's only 10 winners. Which is fine -- I still made my contract. But I could have made 11 tricks. Now to make 11 tricks I need the ♣ finesse. That is not a sure thing.

Be careful when throwing away cards from either your hand or your Dummy. Just because the card is low doesn't mean it is not a winner. Just because the card is high doesn't mean you want to keep it. Figure out which cards are winners and keep them. Figure out which cards are losers and throw them away.