Olivier Hanlan is a major-conference player leaving school after his junior season. That may not turn out well. Leaving after his senior season may not have either. (USA Today)

Each spring when a national champion is crowned, we who follow college basketball reliably turn our collective endeavors toward scolding every non-lottery-track player that announces his intention to leave school early. Comments like “Is there a third round now?” and “Get your passport ready” pop up regularly on Twitter each April.

Basically if I’m a basketball writer and you’re an underclassman who’s not projected to go in the lottery, I’m supposed to tell you to stay in school. The instinct behind that piece of advice is reflexive and genuine. It is also largely unexamined and — in one specific, admittedly qualified and most certainly narrow sense — incorrect.

Start with the realization that this is a uniquely challenging and above all artificial (not to mention unnecessary) bind that we put players in. It is as if someone had come up to me a few years ago and asked me whether I’d like to write for ESPN. Yes, I would have responded, I would like that very much.

“That’s great, John. Now declare that you’re leaving Basketball Prospectus early, and submit your name to be eligible for the ESPN draft. Maybe you’ll be picked, but if you’re not you have to give up what you’re doing now and fend for yourself as best you can.”

Within this artificial and uniquely challenging bind, however, it is demonstrably true that being younger is better. Other things being equal (and caveats will be trotted out, don’t you fret), the longer you stay in school the worse your chances are of being drafted in the first round:

Percentage of first-round picks, 2010-14

It’s easy enough to tell non-lottery-track prospects to stay in school, especially since in most cases such a player is simply facing a choice between when he he will go undrafted. But we should be far more careful about offering the “stay in school” advice in terms of boosting your draft stock. That stock will indeed be boosted in a few instances (particularly with respect to freshmen who become sophomores), but the role of college coaches in player development is vastly overrated and, anyway, you’ll just be competing against a different crop of lottery-track freshmen next summer.

Besides, what really separates seniors isn’t their scarcity relative to underclassmen in the NBA. What really separates seniors — even compared to juniors, much less freshmen — is how late in the first round they’re selected:

Average first-round draft position, 2010-14

The seniors selected highest in the draft of late have without exception been mid-major stars for whom four full seasons were (apparently) necessary to assuage the NBA’s strength-of-schedule doubts: Damian Lillard, Jimmer Fredette and C.J. McCollum. Conversely if you’re a major-conference junior being told that of course you should stay in school, you should know your odds are very, very long.

Of course, being selected late in the first round is still a really sweet deal. But it’s a very rare sweet deal. Each year approximately 1,000 eligible players hit the market having completed their college eligibility, and of that number just four seniors are, on average, selected in the first round of the NBA draft.

Sure, but what about the second round?
There are at the moment 110 guys on NBA rosters who were drafted in the second round. That works out to about 25 percent of the league, and included in that quartile are indeed important players like Chandler Parsons, DeAndre Jordan, and Draymond Green. The question isn’t whether you can stick with an NBA team outside the first round. The question is whether my fellow writers are correct and your chances of doing so are any worse if you leave school early.

For what it’s worth, seniors do absolutely dominate the second round of the NBA draft. Such players provide the largest pool of available non-elite talent.

Percentage of second-round picks, 2010-14

But, as you’d expect, the math here is brutal. Second-round selections comprise half of all draft picks, but just a quarter of all (current) players. There’s a reason the commissioner doesn’t hang around past the 30th pick — many of these seniors chosen in the second round won’t be sticking with an NBA club. Such players have to compete not only with all those oh so fancy first-rounders but also with the 15 percent of the league that has reached the promised land without being drafted at all. (And, naturally, free agency is yet another realm where leaving early is no black mark.)

True, some of these seniors that won’t make the cut do at least have a college degree, and that is surely a benefit. Then again not having a degree doesn’t necessarily spell doom. I’ll spare you the usual examples of college dropouts who struck it rich as entrepreneurs, and point out instead that you can achieve success even in the more mundane vocational precincts where you work for people who do evaluate your credentials. You can be hired as a major-conference head basketball coach. You can be a viable candidate for the presidency. You can even go back to school.

We call leaving school early “declaring for the NBA draft,” but a better phrasing might be “starting a professional basketball career.” By leaving early you’re taking a step toward spending your 20s playing professionally even if you’re not in the NBA — and you most likely will not be in the NBA. Conversely by staying through your senior season you’re giving yourself some additional flexibility for doing something in your 20s besides professional basketball.

In other words this is nothing more than a decision about one’s career path, the kind we all face all the time. And it has always struck me as curious that writers are so eager to throw stones at the professional basketball choice. Receiving an NBA paycheck, even for a short while, is a dream that will elude most college players, but if you really are in the discussion (and not just pipe dreaming) it is true that as a general rule you can maximize your NBA appeal by leaving early. We shouldn’t be so quick to scold.