Mystery feature worth?

So I keep seeing all these slot games advertising “mystery features” or “random bonuses” and honestly I never know how to value those. Like, is it actually adding much to the RTP or just flashing lights and bells that eat more bankroll? I mostly stick to roulette and blackjack, so maybe I’m just suspicious about anything that isn’t super clear on the odds.

Sometimes I get drawn in because those features look fun, but I swear sometimes they never land or when they do, the win is just a couple spins’ worth. With table games, you at least know what you’re getting into, but with slots it feels a bit like they just throw in these side gimmicks and no one knows if they’re really worth chasing. I’m curious if anyone here actually factors these mystery things into their long-term strategy, or if it’s just there for entertainment.