Something that I've discovered is that as the volume of text that I write goes up, the errors increase. More experience hasn't resulted in fewer typos. On the contrary, I make far more small mistakes now than I used to.

It's precisely because I've learned to read and write so fast that I "skip over" the simple parts of sentences, making me oddly blind to certain categories of spelling errors!

Especially when I've gone over the same text over and over, I'll have memorised it to the point that I can skip entire sentences.

This is why you need someone else to step in and read the text for the "first time" and not skip anything.

The same applies to programmers and code review.