Why has our safety play been so poor for so long?

Since 2002, safety recruiting has looked like this: 

2002: None

2003: Ryan Mundy, DB 4*(Transferred) - Quinton McCoy, DB 4*(Injured)

2004: Charles Stewart, DB 3* (Career back-up)- Jamar Adams, DB 3* (Career back-up)

2005: Brandon Harrison, DB 4*(Contributor) - Jonny Sears, DB 3* (Back-up)

2006: Steve Brown, DB 4* (NFL Starter) - Jonas Mouton, DB 4*(Converted to linebacker)

2007: Artis Chambers, DB 3* (Quit)- Michael Willams, DB 4* (Contributor, mainly special teams)- Troy Woolfolk, DB 3*(Contributor often injured) - Donovan Warren - DB 5* (Left too early)

2008: Boubacar Cissoko, DB 4*(Transferred) - J.T. Floyd, ATH 3* (Starter at CB)- Brandon Smith, DB 4*(Transferred)

2009: Vladimier Emilien, DB 4* (Transferred)- Thomas Gordon, ATH 3* (Good starting safety)- Justin Turner, DB 4*(Transferred)

McCoy tore his ACL before ever making it to Michigan. Mundy transferred and eventually figured it out. He is now in the NFL. Charles Stewart and Jonny Sears both were at Cornerback behind Morgan Trent and Leon Hall. I believe Stewart contributed some. Jamar Adams was a serviceable back-up who played many different positions in his time here. Brandon Harirson played in 12 games every year he was here, but was never a star. Steve Brown couldn't figure out angles while at Michigan, but he has had a few good NFL seasons lately. 

Jonas Mouton played linebacker. Artis Chambers quit the team as a back-up. Michael Williams was a solid contributor who mainly played as a back-up and on special teams. He started a handful of games at safety. He was injured often. Troy Woolfolk everyone should know about, often injured but a solid player. Donovan Warren played cornerback, was slower than most people thought, and he left a year too early.

Cissoko, Vladimier, and Turner all transferred. Thomas Gordon was a good safety, whether anyone wants to admit that or not. Not a star, but a good big ten safety. J.T. Floyd mainly played CB. Brandon Smith was a hybrid linebacker who transferred. 

From there I believe most fans understand the story. One look at recruiting pretty easily tells the story. Any high ranked guys usually end up at cornerback. Not a single safety listed as a recruit, all of them were listed as DB. Most were looked at as cornerbacks or safeties, not a lot of safeties coming in that stuck. Some of the guys who did come in as safety recruits transferred out quickly.

A lot of this has to do with Carr to RR transition. From there it has been a while before Michigan could build any kind of depth and give their guys a chance to develop and learn the defense. 

Wilson was a heck of a safety, Thomas Gordon was solid late in his career. Kovacs was good. Delano Hill looks promising. Dymonte Thomas came in as a linebacker trying to become a safety. Cissoko, Vladimir, Cullen Christian, Turner, Dorsey, Vinopal all transferred. Most probably would have been good contributors. Some couldn't get away from off the field issues and others became good starters elsewhere.

Carvin Johnson and Josh Furman were both hybrid guys who couldn't figure out coverage. Yes, Furman had a good season at Ok State playing a hybrid linebacker role. 

2011 saw four guys come in as cornerbacks. 3 stuck at the cornerback position, one transferred. 2012 saw 4 more guys. One is now at linebacker. One is stuck at cornerback and way undersized. One was Jarrod Wilson who has been a good safety. The other a late bloomer in Jeremy Clark who still has a chance to contribute.