Same here – errors jump out at me too. You could argue that minor SPAG errors are not worth bothering about. There is, I would suggest, always a benefit to having another set of eyes pass over your writing.
A few months ago, there was a series of three articles by a chap called, I think, Jacques. It was about sharpening taps, and involved some inventive grinding.
There was commentary in another forum, from some users who had read the first article, but didn’t have the faintest clue what was being done. I must admit, I had to read the article twice to divine that he was chopping off the hard-working end of the tap, then re-grinding the taper to make a fresher end. The confusion came from the lack of an introduction or overview saying just that.
The author launches straight into an account of tap clearance angles – alpha, beta and so forth. Just like with proofreading your own work for SPAG, it sometimes takes that other pair of eyes to point out these things.