Some people are not able to read exactly what is written down, and only what is written down. For example:

"It is very important that we count to six instead of five: One, red, three, five, six!"

Some people will read "four" even though it is not written. But also, some people will understand the whole sentence was a five-count and miss the six. Some won't notice the red.

I wonder how many times I have done this. How many times my brain has filled in the gaps the wrong way, or failed to do.