Almost every trade idea that feels obvious gets rejected, and usually for one of four reasons. Here they are, in the order they bite — and a free game where you can try the offer and see the answer straight away.
This is the rule that kills more ideas than any other, and it surprises people because it has nothing to do with talent. A team already over the salary cap cannot simply take on more money than it sends out — the incoming and outgoing salaries have to land inside a window of each other. That is why a contending team cannot just absorb a star on a big contract with spare parts, and why so many real trades include a player nobody wanted: he is there to make the money work.
Practical version: before you get attached to an idea, check the two payroll numbers. If the gap is large and both teams are over the cap, the trade is dead no matter how fair it looks.
The most common mistake is arithmetic: adding up ratings and assuming the bigger pile wins. It does not work that way, because a roster has only five spots on the floor and one of them being genuinely elite changes every possession. A team trading away its best player is losing something it cannot replace with volume, so it prices that player far above the sum of what you are offering.
Practical version: to get a star you generally need a near-star plus real sweeteners, or a package of young talent and picks that could become a star. Quantity is for filling holes, not for buying the top of a roster.
A rebuilding team does not want your good 31-year-old, however useful he is; a contender does not want your 19-year-old project, however promising. Half of trade-finding is not valuing players correctly — it is finding the team whose plan makes your surplus into their need. When a rival's season collapses or their window opens, their answer to the exact same offer changes.
A first-round pick two years out is worth roughly what the team trading it will be worth then — which nobody knows, and that uncertainty is exactly why it is valuable. If you are genuinely one piece from contending, spending picks is correct: you are buying the years you are good with the years you have not lived yet. If you are not close, you are simply borrowing against a future that arrives anyway.
There is also a rule worth knowing: leagues generally stop teams trading away first-round picks in consecutive future years, so a front office cannot mortgage an entire decade in one afternoon.
Hoops GM is a free browser game with a full trade machine: build an offer, see the salary matching resolve live, get the other GM's honest read on it before you send it, and take his counter-offer if it is better than yours. Fictional league, no download, no account.
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