I always "eat words" when I write. Why is that?

Cause: Your mind gets ahead of your hands. Advice: Don't sweat it. Edit. More Important Question?? Why has the bone in your hand been misplaced?

It's frustrating because it makes you look like you don't know, when you perfectly know and it takes away the strength from what it is you are saying. The reasons are lack of concentration or distractions. It happens to me all the time. There is an idea, then there is the the impulse to write it down, but the mind has already moved on with the idea. The mechanical process of writing is just not compatible with the process of thinking. If you concentrate on the writing you slow your thinking, if you keep up with your thinking your writing becomes error prone. I guess, in principle, there is an optimal "zone" somewhere. If you get distracted you have to find your thread again and that takes energy away from paying attention to details. Both lead to all kind of omissions or wrong spellings like "their" instead of "there" or even an operative word missing in the sentence. That can happen when I am particularly satisfied with my sentence and what I am expressing that I don't bother to look. It helps take a break after you have written what you wanted. And then calmly reread it. Maybe multiple times. I often don't trust myself. If the thought is fresh I will just read over the mistake. Don't do that for every sentence, it will interrupt your flow of thought. As thoughts are evidently elusive it is more important to bring them down in whatever form and then redact it later. You will be able to reconstruct a thought even from error riddled fragments. If you let it go when obsessing with the writing itself you might loose it completely. Come back to it a few hours/days later when the idea has cooled down a bit and you can see the text with more distance.   ---- PS: let's see how many times I will come back to edit this, I have been interrupted 20 times writing it :-)

The hands (or fingers) have a hard time keeping up with the mind.  If what you're writing is fairly automatic (a simple personal message), about a highly familiar topic, or something you have strong feelings about, you might have this happen more often.  Also, fluent writers, who are skilled and practiced because they write a lot, may have this problem more than the less fluent. Unfortunately, spell checkers don't always catch these errors, and if you reread you may miss them too simply because you know what you mean and you're reading quickly, not noticing individual words much. Reading aloud is probably the best way to catch this kind of mistake.  It forces you to go through the text more slowly and to focus more closely on the individual words.

I'm not certain the correct term is "attention bias" but it'll do for now. The human mind is a marvellous thing, even when it's lying to us. One aspect that ties to your issue is the time machine: because of the time it takes us to process stimuli, we predict, often with great accuracy, events that haven't quite happened yet. Catching a ball means predicting where it will be before it arrives and when to close the hand, a few hundred milliseconds before. You're unlikely to notice much of anything around you and it - anything outside that narrow visual window gets relegated to background. That's how magicians fool us, and why eyewitness reports are often inaccurate. So when you miss putting a word into a sentence it's due to this bias. You know it's there because your attention is on what surrounds it. Once you get over believing your own eyes, it gets easier.

I find this a frequent occurrence for me, and one that materializes when I tend to be 'on a roll'. Whether I am writing a faced pace action scene, or  particular dramatic bit of dialogue, if I am deep in my writing zone and the words are rolling off my keyboard, more often than not, I will miss one or two (to be found during the editing stages). It doesn't seem to me to be unusual. I consider it to be part of the writing process when my mind works much faster than my fingers.

You need to get comfortable with writing. Worrying about handwriting and getting distracted by the feel of the pen are some deterrents to fluent written expression. First you write slow. Like real slow. BUT no mistakes. Ideally writing random thoughts would be the best content for what you will compose. as you get accurate at one speed, try writing faster. Your aim is to utilize the parallelism in your brain to control the writing and thinking processes independently. Think of how comfortable you are with vocalizing your thoughts. You don't pause to think and yet you don't make many mistakes.

Dude whenever you are writing then stay focussed on what you are writing and avoid thinking about other things.....one thing which you can practise is that speak out whatever you are going to write...in this way you won't miss the words in between.

Cut yourself some slack. My grandmother would call it "carelessness", just be a bit more mindful and aware of the task at hand, automatically it should reduce. Also, stop being anxious it helps in improving your confidence levels.

I also make the same mistakes. I observed that writing on a bigger screen aggravates the problem