I hear people saying this a ton, aside from the slow face unlock, I haven't experienced many glitches. What am I not doing wrong? Is there a specific gesture to trigger one of these bugs (genuine question)?
It's a death by a thousand paper cuts thing. There is no one bug that can be easily fixed. It's dozens (maybe hundreds) of small annoyances like the keyboard absolutely refusing to register a keypress that goes against it's prediction of what I want to type. Another fun one is I get floods of old notifications randomly usually from phone/messages -- like a voicemail notification from a month ago. I don't even care if Siri doesn't work well or if I have to enter my PIN slightly more often because of FaceID. I just want the fundamentals to work reliably.
I had all kinds of problems like this until i just bit the bullet and did it clean slate, and i haven't had a single performance issue since. Not a single reboot, nothing. The regular iOS11 gripes are still there but nothing truly awful like this
It's a bit like doing a clean install when you order a new laptop right after you take it out of the box. It's usually a good call, even if it's a bit of a hassle