It’s not completely clear yet what brought about Caleb Porter’s departure as manager of the Portland Timbers. Pretty much everyone reporting the story — including Paul Tenorio of FourFourTwo, who originally broke it, and Chris Rifer of Timbers blog Stumptown Footy — has described Friday morning’s news as a surprise, and all of them confirmed that Porter left on his own volition.

Considering the desirable nature of the Portland job and the relative success of their 2017 season, it is not easy to devise reasons for this sudden development. Perhaps something was amiss between Porter and the front office. He doesn’t appear to have had an immediate job lined up, but it’s possible (without any insider knowledge) that he wants an opportunity to fully take the reins of an MLS expansion club.

While Cincinnati, a highly-ranked contender to get a team in 2019 that is located near Porter’s previous gig at Akron, was initially subject of internet suspicion, that rumor appears to have been put to bed for the time being by MLSSoccer.com’s Matthew Doyle in the comments section of his article on the situation. A lot still remains unknown.

We do know that the Porter era has come to an end in the Rose City, after four off-and-on seasons of varying successes. He won Coach of the Year in 2013, leading Portland to first place in the Western Conference, before disastrously failing to qualify for the 2014 playoffs. They won MLS Cup in 2015, though, beating error-prone Columbus on the road in the final. But they missed the playoffs again in 2016 despite a roster featuring many stars from 2015 and even 2013. And then in 2017, they won the conference again.

The 2013-2017 Timbers should be remembered mostly for Diego Valeri, their star designated player. They were mostly successful, with severe disappointments thrown in. You just can’t miss the playoffs in this league with the roster they had.

Their core from this year will be intact for 2018, in all likelihood, and for good reason: it scored a ton of goals and won the freakin’ conference. It’s solid. Valeri, Fanendo Adi, Sebastian Blanco, Darlington Nagbe, David Guzman, Diego Chara, and maybe Alvas Powell and Larrys Mabiala comprise that core, one that includes the likely MVP winner (Valeri) and one of the best midfield partnerships in MLS (Guzman and Chara).

Its undoing this year was depth, and that exposed both the number one flaws of both the front office and Porter. The organization was unable to have suitable backups in place for when players like Powell, Vytas, Guzman, Chara, Blanco and Adi missed significant time — relying on below-par “League Veterans Who Know What It Takes To Win In MLS” as replacements in November isn’t a great strategy.

Lawrence Olum is great and all, but he just can’t adequately replace Chara, who went down with a long-term injury early in the Timbers’ conference semifinal first leg in Houston. Same goes for Amobi Okugo, Dairon Asprilla, Darren Mattocks, Amobi Okugo, Jeff Attinella, Roy Miller, etc. Simply not enough.

In the short-term, Porter was in a tough spot when his players started dropping against the Dynamo. Looking from a wider view, though, he has been continually worse about integrating younger players from the academy and SuperDraft into the first team. The fact that he was punished for it is a sign of the times.

Refer to the tweet linked to above for proof: Portland was not willing to trust young players whatsoever under Portland. They have been the least effective MLS club in the SuperDraft over the past three years and they’ve rarely bothered to look closely at potential contributors from their USL affiliate, Timbers 2.

Maybe the organization has been developing MLS starters through their academy and T2. We’ll never know, because none of them ever received any opportunities. Jeremy Ebobisse, a highly-touted college forward who Portland traded up top draft last January, didn’t receive significant minutes even when Adi went down for the last 10-plus games of the season. Mattocks, 27, played instead.

I’m sure it helped that Porter coached Mattocks at Akron.

MLS as a whole has been trending in the #PlayYourKids direction, shown by Toronto FC’s record-setting regular season, which was led in part by Homegrowns and in-league contributors developed within the first team. Creating linear improvement throughout the roster is now a crucial skill for managers and organizations in this league, and it’s simply not something we saw from the Timbers under Porter.

Porter isn’t a bad manager at all, and the fact that he was able to pull Portland out of the Western Conference mess and grab first-place despite the multitude of injuries was an impressive feat. But he wasn’t winning tactical chess matches very often, and everything described above is significant. I’m not sure where goes from here, but I certainly hope it’s not the USMNT.

The Timbers have to get better at developing and then actually playing youth talent, while allowing that talent to consistently improve. That help solve their problem with depth as well as give them money to spend on, say, a starting center-back.

They have a year or two of that core still left, years in which they realistically should be contending for trophies. Hiring a manager who can do all of the above is the immediate task for a front office with a fanbase to please.

About Harrison Hamm

All things American soccer for The Comeback. Houston Dynamo for SB Nation's Dynamo Theory. Follow me on twitter @harrisonhamm21.