Re: Jesse Winker
Promotions are almost never based on stats, although the stats can be symptoms of the things that are commonly used. Assuming there is available playing time at the next level without taking time away from another prospect, it comes down to how the player's game projects against the upgrade in competition. Example: A player who feasts on fastballs but struggles against any pitcher that can throw a breaking ball for a strike when he is behind in the count might put up great numbers, but he is going to get killed at the next level. He won't be moved up until he starts to show something against the type of pitcher he will see at the higher level. Another player with a more modest set of numbers but without the glaring holes in his game would be deemed more ready. There are examples of both kinds of players everywhere.
You also have to weigh in the player's ability to adjust and the short-term room for growth in his skill set. Example...with some hitters, you can see their performance against certain pitchers and you feel like he has a lightning quick bat and he could still turn it up another notch or two if pushed, and there is another guy who might be putting up better numbers now but he could not handle anything more challenging.
It is all subjective. The Reds would never move any player up a level based on his OPS, although again, the OPS may (or may not) be a symptom of overall readiness to move up.