The game does not have much depth to it, ultimately; there just isn't much to do.
Now, that doesn't make it easy - effort, team building and long-term planning are all incredibly important and keys to success - but that just means that people can quickly become bored and demotivated.
Namely, there aren't that many mechanics and systems to tinker with on a daily or even weekly basis; so, when you just kinda play on, season in and season out, especially without any meaningful improvement, it becomes uninteresting.
Further, with so little (seemingly and directly) possible for a manager to do, it can become quite frustrating to see a lack of success for yourself while others thrive (like the Villains and now the Catchers); people can just get a feeling that someone, well, "figured it all out" and are now so much ahead that you might not even bother.
As implied, there are many potential features and gameplay system changes that could give more depth (and width) to the game, increasing playability in the long-term and allowing for the Managers to be engaged on a daily basis.
This is a completely free game - for a niche interest - that survives off of the occasional donation. The Dev has no profit from it and thus, all passion aside, no real incentive to work hard on it.
IMO, the only way this game can turn around and become something substantial is if:
1. More gameplay mechanics and systems are added/existing ones are developed to have more depth.
2. The game is at least partially re-designed to included limited microtransaction elements (not Clash of Clans "P2W style", more like Rocking Soccer "P2GetSomeConvenience style").
3. The game is released on the Android and iPhone App Stores.
In that scenario, I can easily see the playerbase quickly increasing to ~1000 active users - and staying there, with at least 10% of them contributing with some type of payment on a monthly basis (maybe with some type of VIP membership).
At the end of the day... There are so many crappy, utterly crappy F2P browser/phone games out there - ones with far less quality and made completely cynically, without any passion - that have active playerbases and make loads of money.
QM has the charming and well-made design, thought-out systems and a small but passionate community... It deserves to be successful and make money. Why would it barely survive while hollow crap rakes in the cash?
So, screw it, add some of those F2P elements and have it be successful.
Legacy of the London Dynamo
Season 30 - Sapling 8.
Promotions (first season in new league):
Season 31 - Oak 5.
Season 32 - Iron 4.
Season 34 - Steel 3.
Season 37 - Bronze 2.
Season 38 - Silver.
Season 41 - Gold.
Season 44 - Honour.
Season 48 - Club World Cup 1st Place.
Highest Honour Placement(s):
Season 44 - 5th.
Isle of Man Hood, Gillingham Giants, London Asswinders, London Ravens, Exeter Patronum, Dudley Dursleys...
London Inquisitors (RIP, S24 - S40).