Adam Dunn is finally a designated hitter this year, an inevitability that would have occurred years ago had he played with American League teams that didn't have to worry about hiding his defensive inefficiencies at first base or a corner outfield slot. Dunn is hardly the first bat-only player to be worth big money, and he'll hardly be the last.

Many believe that New York Yankees catcher Jesus Montero is the best offensive prospect in baseball. But the chances of him holding on to that catcher label seem thin. He's well below-average at the position and will likely spend the majority of his big-league career known for his bat alone.

And then there is Bryce Harper. Sure, he's very athletic now, but he's also a 6-foot-3, 225-pound 18-year-old who is far from physical maturity. It's easy to forget that Dunn was once a similar talent. As a teenager, he was a potential Division I quarterback and was similar in size and athletic ability to Harper at a young age, when he was listed at 6-5, 235 in Low-A when in the 2000 season he (believe it or not) had more stolen bases (24) than home runs (16).

Beyond the size, there are also elite-level young hitters consistently moving down the defensive spectrum. Some, like eventual Pirates first baseman Pedro Alvarez, lack athleticism, while others, like Milwaukee's Ryan Braun, just can't seem to find a knack at a position they have all of the tools to succeed at.

Is this new? Is defense overall in baseball declining, and if so, why? I spoke to a number of scouts, executives, and industry insiders about the issue, and the opinions were wide-ranging.

Theory No. 1: Chicks Dig The Long Ball

The offensive explosion of the 1980s seems to have ended the concept of the defensive specialist, especially on a starting-lineup level. But one scout thinks that the overall quality of defense hasn't changed as much as the opportunities granted.

"I'm not sure that, overall, it's getting worse as much as it seems every guy that can produce OPS is now a valued prospect, and they get chances first," he explained. "There are some pretty good defensive shortstops in Double- and Triple-A that are light-bat guys, and they never get chances anymore."

While defensive metrics have advanced, we're still not totally sure how to measure the value of good glove work. But as much as the stats matter, there might also be a cultural aspect to recent developments.

"For such a long time, the game at the major league level was all about offense," said one scouting director. "It's only natural that young players want to copy their idols, and for the most part, baseball has been about the home run."

Theory No. 2: Lack Of Instruction

For the most part, insiders didn't blame players as much as they blamed a system that simply doesn't teach the fundamentals, even at advanced amateur levels.

"One year we drafted three infielders from top college programs, and all three kids told me they got zero mechanical or technical instruction on defensive fundamentals in college," said one team executive. "Yes, they took some ground balls and worked at it, but there was no actual instruction."

That instruction itself is also hard to find.

"You can find hitting, pitching, and personal strength gurus on every street corner," he continued. "But it's really difficult to find competent, knowledgeable defensive instructors outside the professional level."

Theory No. 3: Where Did All Of The Athletes Go?

By all accounts, the 2011 draft class is one of the best in recent memory, and yet, after Florida prep star Francisco Lindor, there are few shortstops. This isn't anything new, as the first rounds of the past three drafts have featured just nine players selected at the position, and of those, seven have already changed positions or have scouting projections of future slides across the spectrum.

"There are few really good college middle infielders, and while there are some options at the prep level, it's not abundant," one industry veteran said. "It's almost as if we are conceding the shortstop position to the international segment of the player acquisition market."

Another scouting executive noted that the depressing truth is that football and basketball still come first for young athletes.

"What is apparent is that fewer athletes in the states are playing baseball, or a least dedicating themselves to baseball," he said. "Still, I don't know if defense is getting worse as much as players are continuing to get bigger and stronger."

Theory No. 4: We're Partially To Blame As Well

As much as baseball below the professional level focuses on the bat over the glove, many admitted that's where the focus is when in comes to player procurement.

"When was the last time a player was drafted high based almost solely on his defensive ability?" asked one scouting director. "Adam Everett?"

That name might make you snicker, but despite batting a miserable .243 AVG/.294 OBP/.348 SLG in his career, he lasted a decade in the big leagues and made more than $10 million in the process. It's good work if you can get it. But will the industry change?

"The Giants had great pitching in the World Series, but nobody talks about how Buster Posey shut the Rangers down," lamented a scout. "I love offense as much as anyone, but the industry seems to not care about defense as long as a guy can produce. You think Brad Emaus would have ever been considered as a major-league second baseman 20 years ago? No way."

Where Do We Go From Here?

The good news is that we are at, or have even passed, the apex of the bat-heavy focus when it comes to scouting, as the dreaded PEDs rear their ugly head once again.

"I think that the emphasis on offense has ingrained itself in the game at all levels," explained a scouting director. "However, with the reduction in PEDs and the new bats in play at the college level, there may start to be more of an emphasis on defense. Over time, that will carry over to the types of players who are value both at the big league level and in the draft."

For the future Adam Everetts of the world, there is hope.

A version of this story originally appeared on ESPN Insider Insider.