Roger Cicala knows a lot about lenses and pushed lens manufacturers to have better testing and quality, he created https://www.lensrentals.com/ because he got sick with low quality checks of lenses:

When I started Lensrentals I had a lot of conversations with service centers that went like this. Me: "That lens you repaired still sucks". Person at service center: "No, it’s within specs". Me: "What are the specs?" Service center: "We can’t tell you". One day, after I raised hell with a factory service manager, he patted me on the head and said, “testing lenses is complicated; you don’t have the background to understand.”

Any of you who has ever seen a physician after someone says something like ‘you wouldn't understand; it’s complicated’ knows what happened next. I had no option but to spend a couple of years buying testing equipment, offering internships to really smart optical engineering students, and developing a lens testing center and methodology that was as good as anything in the industry.

He is also capable of writing about hard topics in a way that most people can understand them.

Anyone interested in camera lenses should read also his previous posts https://www.dpreview.com/members/1329131098