This year's free-agent class is the worst I've ever ranked and written up for ESPN, which now covers 11 offseasons, and I can't remember one being worse before that. There's some outfield help, some adequate catching options and a couple of closers, but that's about it. If you're looking for a midrotation starter, a middle infielder or a third baseman, you're pretty much out of luck. There's no ace on the market or anything close to it. There are almost no high-OBP options. And the class as a whole is old, with many of its best players already well into their 30s. So for most teams looking to upgrade their major league rosters this winter, the trade market becomes the best avenue.
The last two offseasons have shown us that just about anything is possible in the trade market, as we've seen "unmovable" contracts moved (including Matt Kemp's) and face-of-the-franchise players traded (Todd Frazier). Whereas three or four years ago, signing a young player to a long, team-friendly deal meant he was the player least likely to be traded, now it simply increases market interest in his services, especially as industry revenues have increased faster than the market can funnel the gains to players.