They are unprepared for the real world and can't handle it. Tennis could help by, say, putting an age restriction of 18 on the circuits. But don't wait for any sense of responsibility coming any time soon.
Right now the guy with JERK writ large across his back is Australian Nick Kyrgios. The world No 37th-ranked player's latest misbehaviour involves a barb slung at opponent Stan Wawrinka during their match at the Cincinnati Masters this week.
If you don't know the grubby line, Kyrgios said to the Swiss: "[Thanasi] Kokkinakis banged your girlfriend. Sorry to tell you that, mate."
Kokkinakis happens to be another young Australian, ranked No 79.
World No 4 and French Open champion Wawrinka has been linked with the 20-year-old Croat Donna Vekic, world No 128. Neither Wawrinka nor Vekic were impressed by the yob, whose year has been highlighted by throwing a game at Wimbledon, and agitated disputes with match officials.
One umpire was told he was "dirty scum", while a racquet was slammed so hard into the ground it bounced up into the crowd.
"I haven't spoken to Kyrgios. But it's a very disappointing thing to be happening in our sport and I hope it won't happen again because it's not a very good image for our sport," Monte Carlo-based Vekic said.
As for Wawrinka, he sounded vaguely Jung-like: "You write the story, you agree, you disagree, you try to see what is the problem, what is not the problem, what's the limit, what is not the limit.
"No one really sees the consequences for the people involved. That's why it's tough to deal with." Kyrgios had few friends in the changing rooms, he said.
The ATP hit Kyrgios, 20, with a US$12,500 ($18,880) fine for that and a related offence, but he's facing the prospect of further sanctions.
Wawrinka didn't particularly want to discuss the issue this week, which was hard to do as the questions flew thick and fast. "There was a lot of anger in the locker room about what he did ..." he said.
"With one sentence, he can touch and hurt a lot of people. I had a lot of support in the locker room."
Presumably Kyrgios thinks either he's funny or he's the hippest dude on the circuit. Efforts have been made - as they have for Australia's other unruly player, Bernard Tomic - to bring him into line.
The only time Kyrgios has felt any sympathy came when the legendary Australian swimmer Dawn Fraser suggested he "go back to where [his] parents came from". Which are Greece (father) and Malaysia, although he was born in Australia.
Kyrgios seems unable to help himself. With a tradition of brats to follow, he's making every post a winner.
