Sandscript spells it out.

If you go to see your doctor and need a prescription, you will see his or her fingers flying over the keyboard and in seconds a prescription form will slip out of the printer. Very different from the old days when your GP scribbled something illegible on a pad of prescription forms. But it occurred to me that if I was a doctor the prescription would still be illegible or worse still, the patient would receive entirely the wrong drug. I am keyboard dyslexic or perhaps dyspraxic is a better word. If I typed this without the benefit of going back to fill in missing letters and change wrong letters, you would read or perhaps red something like this.
When I was at school, place and time irreleant, hte system decrteed that after first year pupils had to decide between a commercial or pfofessional copurse.
At high school we had to decide whether to take the professional or commercial course in second year. I was twelve years old. All I knew was that I did not want to work in an office and learning typing and shorthand would be boring. None of us knew then that in the future everybody would be using keyboards.
My handwriting is untidy, but I can spell, or thought I could. When you trace your pen across paper you write one letter at a time. On the keyboard your brain races ahead, followed by your fingers, typing the end of the word before the middle. A friend regularly types reports at work about 'clinets', so I know I'm not alone. With my brain and hands under the illusion that I am a typist, speed results in many wrong letters being hit.
It is a wonder that I managed to write a novel 240,000 words long - 'Brief Encounters of the Third Kind'.
But back to the doctors. Prescriptions are not the only words your doctor types while you sit in front of his or her desk. Many patients complain the doctor does not look at them, let alone listen, as he is too busy looking at their notes on the computer screen. I sympathise with the doctor, I could not type and interact with a Human Being at the same time. Due to the angle of the screen and the distance, the patient cannot read their medical details. The doctor types symptoms and advice given onto the records that will be stored for ever, he never seems to falter, though perhaps if we did look we would see a jumble of letters.