[gsej]

I used to pull the code and run it for each PR, as I believed it just wasn't possible to read code adequately. Then I worked with one guy who clearly could read code very well - he found quite subtle issues just by reading it, and having seen it was possible, I put in the effort and learned to do it too. So in my case, my reason for always pulling and running the code was, as you suggest, that I simply wasn't very good at reading code. I still won't hesitate to pull and run code if I need to, but I'm pretty suspicious of code I can't read these days, and usually request it be made clearer.