In the end, they always leave. And Liverpool finds itself immovably stuck in a place where the return of its glory days remains just out of reach. It’s a PR problem, really. The very best Reds don’t think that Liverpool is in the top tier of the world’s soccer teams. So they leave and we never find out if the storied club will ever relive its halcyon days.

Philippe Coutinho is gone. Five years after Liverpool picked him off Inter Milan’s scrapheap for a nevertheless considerable $11.5 million, he’s moving on to Barcelona for a reported $192 million. While not yet official, the transfer would make him the second-most expensive player ever behind Neymar.

The 25-year-old Brazilian has blossomed into one of the world’s best attacking midfielders. And now he’ll be spending the bulk of his prime at a club that isn’t Liverpool, where he became great, to succeed the legendary Andres Iniesta. That’s how it goes at Liverpool. That’s always how it goes.

In the summer of 2015, Raheem Sterling, arguably the most promising player Liverpool had produced since Steven Gerrard, decided he’d rather be at Manchester City. Luis Suarez left for Barcelona the summer prior to form perhaps the greatest attacking threesome in the history of the game with Lionel Messi and Neymar.

In 2011, Fernando Torres left for Chelsea. And while, in retrospect, Liverpool cashing in on the striker when it did was a masterstroke, given his immediate decline, that was hardly apparent then. And a few months earlier, Javier Mascherano had gone to Barcelona to join the core of a budding dynasty.

The prior summer, midfield mastermind Xabi Alonso left for Real Madrid — as did Alvaro Arbeloa, for a pittance, before becoming the regular right back for both Real and Spain. Even the club’s golden boy striker Michael Owen eventually left for Real in 2004.

If even half of those players had stayed, Liverpool’s 21st century history would look very different. Instead, the club that won 11 First Division titles and four European Cups from 1973 through 1990 has been competitive for the league title just a handful of seasons this century. In Europe, meanwhile, Liverpool had a five-year run from 2005 through 2009 where it won the Champions League, finished runner-up once and reached the semifinal and quarterfinal once apiece. But that was 10 seasons ago, and the Reds have been a non-factor in the Champions League since — although they reached the final of the Europa League in 2016.

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Coutinho signed a new five-year contract just 12 months ago. It was the second time in a year that he’d been given a new and improved deal. Nonetheless, Liverpool is powerless to stop his departure. It’s no small feat that it managed to hold onto him when Barca reportedly also came knocking last summer. His transfer seemed inevitable then, but was held off a few more precious months.

Just long enough for Liverpool fans to find out what a scintillating attacking diamond Coutinho could form with Roberto Firmino, Mohamed Salah and Sadio Mane. The sort of attacking squadron that could compete for the Premier League title with another year of seasoning, if only the club could keep them together.

But it can’t. It hasn’t. Coutinho feigned an injury as the deal was hashed out and in so doing made it clear that if Liverpool forced him to stay, he’d make a nuisance of himself. In the end, the players always get their way in modern soccer. They can refuse to play, or give off the appearance that they’re being held against their will. It’s a bad look for their incumbent clubs. Not to mention that it’s much harder to extract top dollar for a player effectively on strike. So most always, clubs like Liverpool capitulate and cash out on their bets.

Coutinho is gone and now manager Jurgen Klopp has to start over in building his attack. Just as his predecessors had to when Sterling left, and Suarez left, and Torres left, and Owen left.

When you’re Liverpool, you can’t buy a Coutinho. Not a fully formed one, anyway. You have to bet on players who might one day become a Coutinho, just as it did with Coutinho. These are gambles. Most don’t work out. And even if they do, they take a few years to pay off. And in the interceding seasons, Liverpool is rebuilding again. Always rebuilding. Only ever rebuilding.

Barcelona can buy a Coutinho and retool. Its core is aging. Messi, Suarez, Mascherano, Gerard Pique, Iniesta and Sergio Busquets are all either 30, about to be, or a few years past that symbolic barrier delineating the end of a player’s prime. So it’s simply replacing them with new superstars.

If Coutinho is marked as an all-time great a decade or so from now, he’ll ultimately be remembered as a Barca player, should things work out as planned in Catalonia. Liverpool, as ever, will just be the club that brought him along in the final phase of his development, before he thrived elsewhere.

Leander Schaerlaeckens is a Yahoo Sports soccer columnist and a sports communication lecturer at Marist College. Follow him on Twitter @LeanderAlphabet.