He's very socially awkward. It's been surprising to find out how much color his personality has. I saw videos of him before but didn't find him that interesting until recently. Like most ratmies, I thought kpop ended and began with btees and had zero interest in other artists. Watching older videos of him, there's something different about him. Besides his huge smile, he's very shy and awkward. Like Sj of btees, he lived with parents and rarely stayed in the dorm. Observe how staff treats him, even as an adult. He's dependent on them for a lot of stuff.
People constantly say that he can't control his mouth. That's something many autistic people struggle with. He says what's on his mind. His mouth has gotten him into so much trouble. Taem1n is like a kid telling their parents business to strangers. What do you think this was on his cheek? Staff might have hit him or it could be bullying at school.