Typing at 60 words per minute (wpm) – no stretch for a good typist – means five or six letters striking the same spot each second. At such a speed, the typist might need to be slowed down for the sake of the typewriter. That is what qwerty supposedly did.
Then again, if qwerty really was designed to be slow, how come the most popular pair of letters in English, T-H, are adjacent and right under the index fingers? The plot thickens.
The father of the qwerty keyboard was Christopher Latham Sholes, a printer from Wisconsin who sold his first typewriter in 1868 to Porter’s Telegraph College, Chicago. That bit’s important… More here.
This subject has been debated many many times and so it continues.