I tried a song over 500 times before I actually completed it once. Then about 100 more plays on that song later, I FC'd it. This was on Hard :p I think Insane has even more retries, and I can still barely pass it...
There's like 5 songs I have in my library that I want to be able to pass on Insane, but can't for some reason. I'm sure I'll be able to pass them eventually, but I do rage whenever I fail. Then it gets worse if I try to retry the song, because then I'll just fail quicker, and quicker... then eventually won't be able to even go 5 seconds in the song without mass failure :/ (which pretty much leads me to just not retry songs, unless I fail within like 10 seconds or so).
I try to FC songs that usually just get Ranked on lower difficulties. I like being ranked high on a song (even though it won't last) :p Other then that, if I play a song that is easy on harder difficulties that I know have no troublesome parts, I'll try to FC it, rage when I miss a beat, finish the song, and move on.
With that said, I don't exactly understand how or why you can get better at osu! just by playing it repeatedly. I just assume I'll be able to FC songs with DT and HR within a year :p (probably a bad assumption though, idk) I play maybe an hr a day, maybe more or less, and usually not in one session either.---------------
just for fun
bg source:
https://www.pixiv.net/en/artworks/72007481