The Miami Marlins are getting some benefit from some hot streaks from guys like Marcell Ozuna, but the big story right now is the ongoing streak of bad hitting from Giancarlo Stanton. Since the start of the Milwaukee Brewers series, he is hitting just .125/.243/.250 with a 37 percent strikeout rate and just one home run and one double as extra-base hits to his name. This has increased the discussion of worry about his game. Here's a good example from Fish Stripes reader Michael Grifasi.
@fishstripes I'm not one to get on ppl when they are cold becuz it happens. But Stanton looks lost. He isnt even close on most of his wiffs— Michael Grifasi (@MikeGrif561) May 18, 2016
@fishstripes im not saying it is. But man does he look bad. And I'm sure he will bounce back w/ 8 HR in 10 games or something.— Michael Grifasi (@MikeGrif561) May 18, 2016
To that I responded that we should be hesitant to believe that any short stretch of games is a true-talent change. When a player is not playing well, it is almost undoubtedly some parts true talent; that is, that player as of right now probably is slightly worse than his true talent. But as researched in The Book: Playing the Percentages in Baseball, streaks are, well, streaky, and more importantly, they are generally not predictive of future performance.
We actually discussed this a few years ago, when former Marlins player Justin Ruggiano was struggling through an 0-for-42 streak of at-bats. And all of a sudden, he wasn't struggling, just like that.
This applies to every player struggling at the plate, unless something mechanical and fixable can be shown to be causing the problem. It is easy to point out that a guy whiffing on a pitch doesn't look good playing baseball, but every whiff is going to look ugly.
You often hear the desire for players to be "consistent," when the reality is that people who say the word "consistent" in that context really want players to be "consistently good." The problem with that is that players are not automatons but rather are humans, prone to the ups and downs any human undergoes. When you go to work, you are not always your best. In fact, there are probably lengthy stretches of time when you may not be up to your very best and stretches of time when you are working at your most efficient.
As a stats person, it feels strange to be the one to argue that players are not their numbers or robots.
As a "stats guy," I get told that "players aren't robots" by fans who also expect them to have robot-like "consistency." (MJ)— FishStripes (@fishstripes) May 17, 2016
No player is consistently at his very best. Over at FanGraphs, they have charting that can track a player's rolling statistics over a certain number of days, and this type of charting shows just how generally inconsistent a player can be. For example, no one would doubt that Mike Trout is among the best players in baseball. But if you take a look at Trout's wRC+ or wOBA over a seven-day period, you can see it goes up and down quite often, and even he experiences longer time periods at lower values.
The dotted line on the chart implies the player's average wRC+ during the entire time period. If you look at any random seven-game run, players will have these sorts of streaky runs in which they dip well below their expectation, just like they have seven-game hot streaks. Compare that to Giancarlo Stanton's seven-game rolling wRC+ tracking since 2013.
This is not even the worse individual streak that Stanton had! He had a similar skid in July of 2014 and another one July into August of 2013. And yet unsurprisingly in both cases, Stanton seemingly bounced back to his typical up-and-down pattern, the same up-and-down pattern even great players like Trout and Miguel Cabrera undergo.
Stanton might appear to be more streaky perhaps because of his strikeout rates. Of course, Stanton is prone to strikeouts, even though that is not necessarily a disastrous thing for a player as good as he is. After all, the fact that he's whiffing so badly and striking out in 36 percent of chances must mean something right? Take a look at the seven-game rolling strikeout rate vacillations for Stanton since 2013.
Just like his batting lines, those strikeouts are going to go up and down. There are stretches where he won't whiff, and stretches where he hits 40 percent rates. And while Stanton is more prone to the strikeout than other hitters, this is again not something isolated to just him.
Unlike your assumptions, players are not consistent. They are not robots designed to produce their average expectation all the time. No player goes through a season without a short period of time slumping and a short period streaking well. Unless there is something mechanically or physically wrong with a player, it is impossible to tell when a streak is a matter of true talent change or whether it is a small blip of variation in a longer season or career.
Of course, there are players who have mechanical problems or injuries limiting their performance. The job of the coaching staff is to identify these things. But just as importantly, like in the example of Justin Ruggiano, it is important for the coaching staff to identify when that isn't the case. Their proximity makes it ideal for them to evaluate this. You and I might watch the Marlins every day, but the coaches are watching the Marlins as a full-time job, during games and before and after. They have a lot more information than we do, and our memories are not tied just to baseball. We have to be careful and really produce evidence before we make assumptions about changes in true talent based on small samples of information.
In short, everybody is inconsistent, so try not to worry too much.