Why NFL trades are so rare

Fans love the idea of trades.

The right addition can throw a team over the top. Or, if things are going poorly, a team can dump a guy for a draft pick. And nothing creates hope like draft picks.

Here’s the thing: Dumping players with expiring contracts for picks (or prospects) is a baseball thing or a basketball thing. Last year’s deal between the Raiders and Bengals for Carson Palmer was the rare major deal.

Such things are uncommon in football, where receiver Mike Thomas going from Jacksonville to Detroit for a pick qualifies as significant.

More common are deals that don’t ever come together.

Teams generally don’t want to trade for a guy with an expiring contract -- odds are they won’t be able to extend him and will have given up a pick for a rental.

Teams generally don’t want to trade quality players with expiring contracts, because they hold out hope of re-signing the player, and likely get a compensatory draft pick if they lose him.

Why else don’t trades usually trend?

ESPN.com's Andrew Brandt points to changing schemes, cap implications and fear of guys who are available.

If your huge hole doesn’t match up just right with someone else’s sale, the most likely thing we’ll hear as Thursday's deadline approaches are crickets, like the one currently making music in the Titans’ press room in Nashville.