I think they should rename diabetes “irony.” For me, the disease is nothing but irony. I can do EVERYTHING right, count every carb, take insulin exactly as prescribed, etc and I will still sometimes get wacky BGs, like that random 300 in the middle of the day for no particular reason. And then there are the SWAG days, the days where I just guestimate everything and hope for the best, and my BG is almost flatlined at 110. Go figure. This disease makes absolutely no freaking sense at times.
You expect it to make sense??? When even biologists and chemists and doctors don’t know what exactly is going on? You’re an optimist for sure! 
I think I expect it to make sense because endos always seem like it should make sense, like there should always be this perfect linear correlation between everything I do (insulin, eating, exercise) and my BG. I generally like the practice I go to, and I think this is an issue on a larger scale with endos. But they often fail to realize the inherent variability of T1 diabetes when you’re trying to just live a normal life.