Good Post, and I hope no members gets caught when an MOT failure is due to something trivial.
My car was 6 years old when I bought it 5 years ago and it had three MOT fails in 6 years with every one being due to a tree problem -- I used Vehicle Smart, a free app to make the check.
I found that quite incredible. A tyre depth gauge can be had for a few quid. My car has had 4 MOTs and all passed with not even an advisory.
Peter.