I mean, we all go in to a new story uninvested, right? I know nothing about this story, therefore I'm not invested in it, but I'll read/watch it if it's good.
Conversely, investment is pretty much the opposite. I know A LOT about this story/world/franchise, therefore I'm VERY invested in it, so I'll still read/watch it if it's NOT good :'D
Of course, to get me invested in it in the first place, it had to start out good, but I can't drop it even after it dips down to mid because of my investment. I can't leave things unfinished; it just feels bad! I need closure on the world and characters I grew to care about!
I also consider myself super picky, but more in the sense that I don't get into mid stuff in the first place. I don't even get into stuff that starts out good; it needs to be absolutely amazing to the point it haunts my waking life if I don't go back to it and see what happens next.
But one exception to this is if I'm doing research for my own stories. I'll gladly comb through stories that explore similar themes/aesthetics/genres, most of which are mid. In fact, I like to have a variety in quality for these 'study stories' because it gives me a fuller perspective on not only what to do but also what not to do and what could be improved on and pushed further :]