Duke’s magic ran out in its 68-67 loss to Michigan State on Sunday. After surviving nail-biters against UCF and Virginia Tech in the previous two rounds, the Blue Devils were the ones on the wrong side of the biggest plays in the final minute. It was the second consecutive year that a Duke team with multiple freshmen destined to be NBA lottery picks lost in agonizing fashion in the Elite Eight. Coach K hasn’t made a Final Four since winning it all in 2015, despite having 11 first-round picks in the NBA draft, if you count this year’s group, in that span. There is an element of luck in advancing through the NCAA tournament, but the way that Duke lost highlighted the downsides of relying so heavily on one-and-done players.

This group of Blue Devils had been living on borrowed time. It didn’t matter how dominant freshman superstar Zion Williamson was in the postseason. His numbers in four games (26.0 points on 61.6 percent shooting, 8.5 rebounds, 1.8 assists, 1.5 steals, and 1.8 blocks) were right in line with his historic regular-season production, but Duke never figured out how to build a balanced team around him. Michigan State, like every other team the Blue Devils faced over the past two weeks, packed the paint with defenders and swarmed Zion almost every time that he touched the ball in the half court. One player can do only so much. A team still needs counters when the defense double- and triple-teams its best player.

Zion is an anomaly in more ways that one. Even the most highly touted freshmen tend to come into the NCAA without his level of polish. RJ Barrett and Cam Reddish, his two one-and-done teammates, had more inconsistent freshman seasons, and the holes in their games were on full display Sunday. Every good play that Barrett made was balanced by a bad one: He had 21 points on 7-of-17 shooting, and six assists and seven turnovers. He’s a streaky shooter who plays with blinders on, and he went 0-for-3 in the final minute, taking difficult shots in traffic instead of moving the ball. Reddish was practically invisible, with eight points on 2-of-8 shooting and one assist and two turnovers. He came off the bench after missing the previous game with a knee injury, but he struggled even when healthy this season.

The Blue Devils got even less from freshman point guard Tre Jones, who finished with four points on 2-of-5 shooting. Jones, an elite recruit in his own right, may have to return to school after losing confidence in his outside shot to the point that defenses stopped guarding him on the perimeter. He shot only 26.2 percent from 3 on 2.9 attempts per game this season. Duke’s inability to space the floor has been its Achilles’ heel all season. The team was no. 25 in the country in 3-point attempts (23.8 per game) and no. 328 in 3-point percentage (30.8). The best way to use an interior player like Zion is to collapse the defense and create open 3s for his teammates, but none of his teammates could make those shots.

Duke couldn’t afford for even one of its star freshmen to underperform. There was no margin for error in their roster. The Blue Devils didn’t return a single player from last year’s team who averaged more than four points per game, and the limitations of their supporting cast prevented Coach K from having much flexibility over the course of the game Sunday. He never developed much trust in any of his three perimeter reserves (sophomores Jordan Goldwire and Alex O’Connell and junior Jack White) so he never went small against Michigan State. He alternated between juniors Javin DeLaurier and Marques Bolden at center for all 40 minutes, and neither had the shooting ability to open up the Spartans defense.

It was the same story for the Blue Devils last season, when their starting lineup was made up of one senior (Grayson Allen) and four freshmen (Marvin Bagley III, Wendell Carter Jr., Gary Trent Jr., and Trevon Duval). While all four were consensus top-15 recruits, only Bagley and Carter lived up to expectations. The backcourt of Trent and Duval could not handle their share of the burden. They couldn’t space the floor or take care of the ball for their star big men, and they combined to shoot 4-of-16 from 3 with four turnovers in their 85-81 loss to Kansas in the Elite Eight. Not every five-star recruit is destined for big things. Trent was taken with the no. 37 overall pick in last year’s draft and has barely played as a rookie. Duval went undrafted.

It’s almost impossible to develop a supporting cast when so much of the team turns over on an annual basis. Duval and Trent would probably have been better off returning to school rather than declaring for the NBA draft before they were ready to contribute at the next level. Their problem is that they were forced out by this year’s recruiting class. Trent would have come off the bench behind Barrett and Reddish, while Duval would have had to fight for playing time with Jones. Whatever NBA buzz they still had would have disappeared if their production had slipped from their freshman to sophomore seasons. They would have had to stay in college until at least their junior year, when they would have been yesterday’s news at a school that regularly reels in the top recruiting class in the country.

Not every recruit that Duke signs expects to go pro after one season. The issue for the ones who do stick around is that the identity of the team changes so dramatically each season that there is no continuity within their roles. Coach K has to start from scratch each summer. Last season’s team was built around two more traditional big men (Bagley and Carter) who struggled to defend in space, so he played a zone and slowed the tempo (no. 105 in the country in pace) to pound the ball inside. This season’s team was built around three 6-foot-7 players with inconsistent jumpers, so he played pressure defense and tried to speed up the pace (no. 27 in the country) to get out in transition. It’s no wonder his bench couldn’t keep up. Players without as much natural talent need to learn to play within a system on both ends of the floor.

A program built around one-and-dones has to maintain as much flexibility as possible to maximize the strengths of each recruiting class. A recruit trying to maximize his NBA draft stock needs to go somewhere without returning players who will eat into his minutes and field goal attempts. Playing with a bunch of upperclassmen isn’t necessarily a good thing for those players. Just look at UNC freshman Nas Little, who was as highly regarded as Zion, Barrett, and Reddish coming out of high school. He averaged 9.8 points per game on 48.0 percent shooting this season while backing up two All-ACC senior forwards: Cam Johnson and Luke Maye. Little, once projected as a top-five pick, will be lucky to sneak into the lottery, and his fate will be used against the Tar Heels in future recruiting battles.

Duke needed a player like Quinn Cook, a senior combo guard on their 2015 NCAA championship team who is now playing for the Warriors, on this year’s team, but the structure of its program makes it hard for a player who wasn’t a top-15 recruit to stick around. Cook averaged 4.4 points per game as a freshman in the 2011-12 season, before the school became a one-and-done assembly line, and gradually grew into a bigger role in four seasons in college. The Blue Devils have had a different point guard in each of the past four seasons, churning through freshmen who never had a chance to get comfortable before being shown the door to make room for the next highly touted player. A huge part of being an NCAA coach is player development, which almost never happens at Duke anymore.

Not much will change next season, either, when the Blue Devils will once again have one of the best incoming classes in the country. Their highest-rated incoming player is Vernon Carey Jr., a more traditional big man who will make Bolden and DeLaurier, the only two non-freshmen to play more than three minutes against Michigan State, redundant. Bolden, a five-star recruit in the class of 2016, was supposed to be part of a one-and-done dream team with Jayson Tatum and Harry Giles. Every school in the country wanted him coming out of high school, but his growth has stagnated at Duke as he has taken the back seat to the next group of elite freshmen. Bolden could theoretically provide senior leadership next season, but his experience will be only so valuable if he’s playing a small role off the bench.

Coach K has come a long way since the dawn of the one-and-done era more than a decade ago, when he fielded senior-laden teams and was regularly beaten by North Carolina and Kentucky for the best recruits. But turning his program into the premier NBA factory in the country has come at a cost. He has been to only one Final Four and won one NCAA championship since he reeled in Kyrie Irving in 2010-11, which seems like a lot until you compare it with the rest of his résumé (five NCAA championships and 12 Final Fours) in 39 seasons at Duke. This has been the least successful of any era of Duke basketball since he took over in Durham, and a coach obsessed with legacy will be remembered by a generation of fans as someone who never got the most out of his players.