At a certain age the minor leagues transform from a learning tool to a death sentence.
I believe that age is 27.
If you're 28 or older and still getting the bulk of your at-bats or innings in the minors it might be time to hang up those cleats. But if you're 26 or younger and struggling to get at-bats or to get batters out in the big leagues, there's nothing wrong with spending some time in Triple-A to hone your craft.
This article is intended to focus on that younger generation of guys that still have time to turn their careers around.
Are there guys with considerably worse statistics than these 10 players? Absolutely. But no amount of time in the minors is going to help a 33-year-old journeyman like Jeff Keppinger remember how to draw a walk.
*All statistics are courtesy of ESPN.com and FanGraphs.com and are accurate through the start of play on Friday, May 17.