Bo Ryan departs; who from this golden era will follow?

— -- After a Wisconsin Badgers practice last season, Bo Ryan sent his players to the margins of the Kohl Center court to greet the war veterans he'd invited to the team's practice facility. They mingled with the soldiers and their families.

Ryan, who announced on Monday that the 2015-16 season will be his last, joined them. He shook hands, shared stories and made them laugh.

Ryan's father, Butch, fought in World War II, so the significance of a connection to the military always struck him as valuable and worth forging throughout his coaching career. Those genuine, off-camera moments rarely emerged before Wisconsin's run of back-to-back Final Four appearances. Throughout that boon for his program, Ryan offered glimpses of the humorous, sarcastic and down-to-earth layers of his personality -- one that folks often mistook as gruff, thanks to his demonstrative mannerisms on the sidelines.

But soon, and not long after Wisconsin became a national player under his guidance, he'll depart.

No more midgame banter with officials who've rarely called a foul against the Badgers that he agreed with. No more candid postgame news conferences.

Ryan, who will be coaching his 17th season as a Division I head coach and 32nd overall in 2015-16, is not alone. Some of the game's tenured coaches will also see their terms come to an end in the near future. Just a few days ago, Syracuse announced that Mike Hopkins would succeed Jim Boeheim, 70, when the Orange's longtime leader retires in three years. Steve Fisher at San Diego State and Larry Brown at SMU have created similar succession plans with their associate head coaches -- Brian Dutcher will take over the Aztecs, Tim Jankovich the Mustangs.

Mike Krzyzewski's youth and spring belie his age, but one day, the 68-year-old will leave Duke. Roy Williams, whose UNC program is battling through an academic scandal, won't remain forever. Rick Pitino has fought retirement rumors for years. Not now, he says. At some point, however, he'll hang up his $5,000 suits and exit Louisville and the game.

Ryan's retirement announcement is a reminder of the changing climate within college basketball. There is this inherent attraction to rapid risers, the young coaches who secure seven-figure salaries and street cred before they discover their first gray hairs.

Shaka Smart, 38, coaches at Texas now. Steve Prohm, 40, followed Fred Hoiberg at Iowa State. Michael White, 38, will coach the Florida Gators now that Billy Donovan has turned pro. Richard Pitino was just 30 years old when Minnesota hired him in 2013. Kevin Ollie led Connecticut to the 2013-14 national championship, when he was 41.

It's refreshing to see the game reboot with talented, new faces. Yet it's easy to forget the experienced coaches who've maneuvered through the evolving collegiate landscape for decades.

They'll face the same predicament that Ryan encountered after his team's loss to Duke in the national title game in April.

Is it time to go?

"[West Virginia] is it for me," Bob Huggins told FoxSports.com last year. "I'll retire when I don't think I can do it anymore."

But Jud Heathcote, Nolan Richardson and Lute Olson would all tell Huggs that they still twitch at tipoff because the desire and know-how are the last traits to get the memo. If athletic directors always trusted coaches to make those calls, how many of them would ever leave?

Ryan controlled his departure. Sometimes, however, the sunset comes early.

The era of big dollars and ambitious administrations has dictated the fate of many coaches in their 50s and 60s who figured they had a few years left.

Health issues have encumbered others.

The game has not yet healed from the death of Rick Majerus.

The end comes suddenly in college basketball, much like Ryan's announcement. A source close to the program told ESPN.com that he spent the weekend with Ryan, who never mentioned anything about retirement.

In the coming years, there will be others like him, though. Some will leave by choice, others not.

They'll linger around their former programs, if allowed to, and make appearances on Jumbotrons whenever they decide to come back and attend games. In those early years after retirement, they'll sign autographs, write books, speak to civic groups and play in charity golf tournaments.

And then, something odd but predictable will happen. They'll fade. From our memories and conversations.

They'll become the subjects of occasional questions: "How's Coach doing these days?"

Then, we might look back and wonder if we recognized the full significance of their final episodes. Their accomplishments and longevity. Their adaptability and resilience.

Ryan used to scout players in tournaments staged on blacktop surfaces. Now he sends text messages to kids who won't grab a basketball unless they're competing in air-conditioned gymnasiums. But he evolved. Ryan led UW-Platteville to four Division III national championships in the 1990s, and two first-round picks in last week's NBA draft, Sam Dekker and Frank Kaminsky, guided Ryan's Badgers to Final Fours in 2014 and 2015.

After next season, Ryan will retire.

His veteran peers in the coaching profession eventually will move on, too.

They'll regret those decisions.

Not the coaches, but the folks around them, who will ask themselves how it all ended so soon.