Why is there so much inconsistency in random drops?

[Firebeard.1746]

There are some metas with lots of monsters with a real loot table with the chance to drop t6 mats and/or small amounts of copper/silver and then there's activities like Convergences and the Cold War pre event where there's no loot whatsoever. What gives? I'm not entirely sure that a convergence has more monster kills than what I would consider equal to a monster packed meta. I'd rather they capped farmable loot in those than just not having it at all (I see convergences could probably be farmed for drops if they had them, but I don't think that's a good reason, there needs to another way). it's weird to have stats like MF and gold find but create so many situations where it's useless. 

There are some activities where the random drops give a huge payout, which I like. it makes me feel good for investing in developing my account. 

[Entara.3075]

Dragon Storm, Convergences and those like it give you the rewards at the end of the meta based upon participation. Some like Convergences and Drizzlewood Coast also have associated repeatable achievements that give rewards.

For example in Convergences you get more rewards via achievements for every 25 turrets you kill, every 5 catapults destroyed, every X creatures killed, etc.

[Blood Red Arachnid.2493]

They started making events like this to stop players from purposefully stalling events to grind loot.  This reach its peak shortly after the champion loot bag update, where people would repeatedly fail the meta events to farm champs.  It's far easier to stick all the rewards at the end instead of coming up with some arbitrary DR system for every event in the game.  

[Astralporing.1957]

6 hours ago, Firebeard.1746 said:

There are some metas with lots of monsters with a real loot table with the chance to drop t6 mats and/or small amounts of copper/silver and then there's activities like Convergences and the Cold War pre event where there's no loot whatsoever. What gives? I'm not entirely sure that a convergence has more monster kills than what I would consider equal to a monster packed meta. I'd rather they capped farmable loot in those than just not having it at all (I see convergences could probably be farmed for drops if they had them, but I don't think that's a good reason, there needs to another way). it's weird to have stats like MF and gold find but create so many situations where it's useless. 

There are some activities where the random drops give a huge payout, which I like. it makes me feel good for investing in developing my account. 

The general rule for that is that one-time/limited spawn event mobs do drop stuff, but infinite spawn ones do not. Of course, Anet being Anet, you can't expect 100% consistency here, but that's still mostly correct.