First off, just from being in my empty pocket for 2-3 days, the screen was covered in scratches that made it difficult to see a portion of the screen in direct sunlight. I've never had this experience with any other phone.
Then I dropped my S8 from less than a foot and it cracked the glass on both the front and back of the screen. I haven't dropped my iPhone X yet, but based on my experience with recent iPhones it can probably take a lot more abuse.
The S8 also had some pretty annoying design/UX flaws. The fingerprint reader placement next the camera was amazingly stupid, and everything related to Bixby has been somewhat of a disaster. I had tried to reprogram the Bixby button to do something useful, but then it was still slow and Samsung insisted on breaking that functionality repeatedly in updates. They ought to know well enough that nobody wants to use their stupid assistant. Or cover their camera with fingerprints.