Have you ever stared at a word for so long that it starts to lose meaning? The letters in the word, in the order they are in, seem strange and unnecessary all of a sudden.
"Sudden" suddenly is a strange way to spell "sudden". As if the s-u-d- with the d-e-n doesn't appear as it is on paper or screen to mean what the word is in my head.
Looking at it, the S with the U moving so quickly to the DD is crass. Its too onomatopoeic. 'Sud' should have some silent letters or an extra O, to make it look more rich, more full, more encompassing. Otherwise, I would use "rapid" or "fast", if I wanted something that looked like a quick and dirty excuse of a word for speed.
The word is not the word when I see it spelled and written. It has less than the esteem I hold for the word inside myself.
Isn't that strange, when that happens?