possible image recognition bug

Running Ios 14.2 on an Iphone 10s, I frequently have to restart Voiceover to get image descriptions working correctly. I'll get a vague description, like "screenshot of a social media post" but if I restart VO I'll get a much clearer one. This will work on 3-4 pictures and then I'll need to restart VO again. I've had this problem since at least 14.1. Is anyone else experiencing this?