MWO

The initial development window for MWO was promising. The problem is that their development schedule began moving slower than an advancing glacier, and no real vision for how they were going to accomplish their lofty goals. The developers had no real understanding of meta-game balance or their game in general and no effort was made to develop inter-class team based mechanics. They see Assault mechs as top-tier avatars which makes any attempt at balancing utterly futile. There's no point even carrying a conversation with them about it, it's completely fucked.

PGI completely fucked up what might have been a viable mech simulator, and turned what was a minimally acceptable product into something I actively rejected and stopped playing. I mean for fucks sake, it's a free game I used to have fun with.

    No tonnage based matching/balancing to keep teams from stacking with disproportionate forces.
    12vs12 fucked balance making it impossible to come from behind once a snowball started.
    Complete inexperience/ incompetency with their game code resulting in repeat claims of something being "impossible" that other studious had no problems finding solutions to. Hell they added DX11 2 years late and it still didn't make the game look any better - Alpine's textures still look like muddy low-res shit.
    A tendency to return to "fixed" problems and non-issues rather than making progress in new areas, adding in useless arbitrary mechanics like ghost heat as a universal fix-all instead of addressing the underlying chassis problems and game mechanics that made it an issue.
    A lack of vision/planning and a desire for quick-fixes that eventually degraded their game. LRM's too powerful? Well fuck. Better give every mech AMS. Oh fuck that just ruined the entire point of the otherwise mediocre AMS mechs didn't it? Oh well, who cares- wait, the missiles are too weak now? Well better boost missiles again because now they're not doing enough damage. Oh fuck now it's a missile apocalypse with everyone carrying 4-6 LRM launchers. Better restrict how many LRM's can be fired at once, that'll solve it. Hm PPC's not registering? Well we should decrease their heat so at least people can fire them faster to make up for the loss in damage. Oh PPC's work now? Better keep their heat low because fuck you. Wait, now mechs are dishing out 55 damage in one pin-point shot (enough to kill or cripple most mechs in 1-2 hits)? Better restrict how many PPC's can be fired at once (don't worry, now it's just down to slower salvos of 35 damage while they move in and out of cover). Mechs generating too much heat? Add Double Heat sinks that players must grind for to be viable (Meanwhile Double Heat Sinks made it possible to run ridiculously high damage builds and save tons of weight and heat that should have been used to balance out builds). Absolutely no plan for their mechanics. They abandoned their original mediocre WoT scheme for absolute chaos and never recovered.
    Completely unresponsive to balancing problems that should have taken 10 minutes tweaking an xml file to adjust left the game ruined for months.
    Awful development pipeline meant the company resisted or was unable to make major changes to the game. I mean, just look at Alpine. A wide open map with no cover, gametypes that encouraged clumping up, and weapon meta that emphasized heavy salvos of long range weaponry to incapacitate most enemy units in 2-3 shots.
    A willingness to relegate some mechs to the shit-heap because adjusting mechanics to make more chassis viable wasn't in the design document. The Awesome should be a PPC fridge capable of laying out sustained long-range fire. Instead it's a tubby mediocre 80 Ton Assualt mech with bad hardpoint placement that is outperformed at its central job by other mechs.

The tragedy is, for like 6 months to a year after it went "Open beta", the game was actually fun. Their iterative design actively ruined a game I didn't mind spending a little money on to support. All of these problems either would be non-issues at better companies, either through avoidance of whatever situation made it a problem in the first place like a work bottleneck or bad code, or through dev experience helping them correct the problem before it poisoned the community.