Progression will not be measured by just success or failure it’s more layered and complex. I can see the benefits and importance of it within a working system and it is very often the difference between high achievement and average.
Above part is why Arteta remains at the club because you unknowingly answered the question.
When he leaves progress will stop and the new manager will begin a new process/ progression cycle.
More progression nonsense and excuses to hide behind failure.
If you Actually look at season upon season and what realistically Arsenal have done? What exactly is their to current show for it.
19/20 - Arteta wins FA cup. Finished 8th
20/21 - Realistically Arsenal could have pushed for a Europa league spot, won the europa league, or domestic cups. They didn't none of those - failed season
21/22 - not in Europe, playing 1 game a week mainly. Realistically Top 4 finish or domestic cup could have been achieved. Bottled top 4 - Failed season
22/23 - oddegard, xhaka, ramsdale all said before start of season. We want to win Europa and make Top 4. Realistic targets. Arsenal bottled the league, didn't win europa. But from a Realistic point of view they made top 4. - 1 Target met, 1 not met
23/24 - Arsenal go big in transfer market. So winning titles was a Realistic target. CL, 1st season back so we're never going to win it. - failed to win title, achieved the best they could in CL
24/25 - A team capable of winning title. Also wining domestic cup and having a go at getting further in CL.
So far not in title race and embarrassing in domestic cups
So for all the dressing up of progress, ultimate on Realistic targets, Arsenal so far have met 1 which was making Top 4 in 22/23 and even thats not a trophy.
Arsenal after 5 years of this phase 1,2,3 4,5 nonsense at stage where judgement is on what you win.
More points, more goals, more excitement or any other nonsense variables don't mean anything at this stage.
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When Arteta leaves progression will stop?


based on what?
A new process will process will be begin.
You should apply for a job as a PR merchant at Arsenal
Did progression stop at Liverpool when klopp left?
This nonsense like your acting like the club will be in trouble in Arteta goes, a manager that's achieved Jack diddly squat since winning FA cup
You think Liverpool or Man city fans are celebrating progression or actually winning trophies.